Disclosure Minimum Future Lease Payments For Non Cancelable Leases [Abstract] Disclosure - Minimum Future Lease Payments for Non-Cancelable Leases [Abstract] Remainder of 2015 Operating Leases Future Minimum Payments Due Remainder Of Period Operating Leases, Future Minimum Payments Due, Remainder of Period 2015 Operating Leases, Future Minimum Payments, Due in Two Years 2016 Operating Leases, Future Minimum Payments, Due in Three Years 2017 Operating Leases, Future Minimum Payments, Due in Four Years 2018 Operating Leases, Future Minimum Payments, Due in Five Years Thereafter Operating Leases, Future Minimum Payments, Due Thereafter Total minimum lease payments Operating Leases, Future Minimum Payments Due Notes To Financial Statements [Abstract] Notes to Financial Statements [Abstract] Stock-based Compensation Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Common Stock Repurchase Share Repurchase Program Disclosure [Text Block] Share Repurchase Program Disclosure Statement of Financial Position [Abstract] ASSETS Assets [Abstract] Current assets: Assets, Current [Abstract] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Marketable securities, short-term Available-for-sale Securities, Debt Securities, Current Accounts receivable, net of allowances for doubtful accounts and returns of $1,803 and $1,563, respectively Accounts Receivable, Net, Current Inventories Inventory, Net Prepaid expenses and other current assets Prepaid Expense and Other Assets, Current Deferred Tax Assets, Net, Current Deferred Tax Assets, Net, Current Total current assets Assets, Current Marketable securities, long-term Available-for-sale Securities, Debt Securities, Noncurrent Property, plant and equipment, net Property, Plant and Equipment, Net Goodwill and intangible assets, net Goodwill Deferred tax assets Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Other assets Other Assets, Noncurrent Total assets Assets LIABILITIES AND STOCKHOLDERS' EQUITY Liabilities and Equity [Abstract] Current liabilities: Liabilities, Current [Abstract] Accounts payable Accounts Payable, Current Accrued liabilities Accrued Liabilities, Current Deferred revenues Deferred Revenue, Current Total current liabilities Liabilities, Current Taxes Payable Taxes Payable Other long-term liabilities Other Liabilities, Noncurrent Total liabilities Liabilities Commitments and contingencies (Note 6 and 7) Commitments and Contingencies Stockholders' equity: Stockholders' Equity Attributable to Parent [Abstract] Preferred stock, $0.0001 par value (5,000 shares authorized; none issued) Preferred Stock, Value, Issued Common stock, $0.0001 par value (200,000 shares authorized; 79,564 and 80,205 issued and outstanding, respectively) Common Stock, Value, Issued Additional paid-in capital Additional Paid in Capital Accumulated other comprehensive income (loss), net Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated deficit Retained Earnings (Accumulated Deficit) Total stockholders’ equity Stockholders' Equity Attributable to Parent Total liabilities and stockholders’ equity Liabilities and Equity Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Expected term (in years) Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Risk-free interest rate Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Expected dividends Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Weighted average fair value at grant date (USD per Share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Disclosure Net Revenues By Geographic Area [Abstract] Disclosure - Net Revenues by Geographic Area [Abstract] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] Statement, Geographical [Axis] Geographical [Axis] Segment, Geographical [Domain] Geographical [Domain] United States UNITED STATES the Netherlands NETHERLANDS Other international Other International [Member] Other International [Member] Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Net revenues Revenue, Net Disclosure Credit Facilities Additional Information [Abstract] Disclosure - Credit Facilities - Additional Information [Abstract] Line of Credit Facility [Table] Line of Credit Facility [Table] Credit Facility [Axis] Credit Facility [Axis] Credit Facility [Domain] Credit Facility [Domain] Revolving Credit Facility [Member] Revolving Credit Facility [Member] Letter of Credit [Member] Letter of Credit [Member] Lender Name [Axis] Lender Name [Axis] Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Wells Fargo [Member] Wells Fargo [Member] Wells Fargo [Member] Line of Credit Facility [Line Items] Line of Credit Facility [Line Items] Line of credit, available borrowings Line of Credit Facility, Maximum Borrowing Capacity Unrestricted Cash Deposit Unrestricted Cash Deposit Unrestricted cash deposit. Debt Instrument, Basis Spread on Variable Rate Debt Instrument, Basis Spread on Variable Rate Line of Credit Facility, Amount Outstanding Long-term Line of Credit Disclosure Computation Of Basic And Diluted Net Profit Per Share Attributable To Common Stock [Abstract] Disclosure - Computation of Basic and Diluted Net Profit Per Share Attributable to Common Stock [Abstract] Net income Net Income (Loss) Attributable to Parent Weighted-average common shares outstanding, basic Weighted Average Number of Shares Outstanding, Basic Dilutive effect of potential common stock Weighted Average Number Diluted Shares Outstanding Adjustment Total shares, diluted Weighted Average Number of Shares Outstanding, Diluted Net income per share, basic Earnings Per Share, Basic Net income per share, diluted Earnings Per Share, Diluted Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas [Table Text Block] Disclosure Long Lived Assets By Geographic Area [Abstract] Disclosure - Long-Lived Assets by Geographic Area [Abstract] MEXICO MEXICO Long-lived assets Long-Lived Assets Disclosure Segments And Geographical Information Additional Information [Abstract] Disclosure - Segments and Geographical Information - Additional Information [Abstract] Number of reportable segments Number of Reportable Segments Disclosure Inventories [Abstract] Disclosure - Inventories [Abstract] Raw materials Inventory, Raw Materials, Net of Reserves Work in process Inventory, Work in Process, Net of Reserves Finished goods Inventory, Finished Goods, Net of Reserves Total Inventories Disclosure Summary Of Financial Assets Measured At Fair Value On Recurring Basis [Abstract] Disclosure - Summary of Financial Assets Measured at Fair Value on Recurring Basis [Abstract] Fair Value, Assets and Liabilities Measured on Recurring Basis [Table] Fair Value Assets And Liabilities Measured On Recurring Basis [Table] Fair Value, Assets and Liabilities Measured on Recurring Basis [Table] Fair Value by Measurement Frequency [Axis] Measurement Frequency [Axis] Fair Value, Measurement Frequency [Domain] Fair Value, Measurement Frequency [Domain] Fair Value, Measurements, Recurring [Member] Fair Value, Measurements, Recurring [Member] Fair Value, Hierarchy [Axis] Fair Value, Hierarchy [Axis] Fair Value, Measurements, Fair Value Hierarchy [Domain] Fair Value Hierarchy [Domain] Quoted Prices in Active Markets for Identical Assets (Level 1) Fair Value, Inputs, Level 1 [Member] Significant Other Observable Inputs (Level 2) Fair Value, Inputs, Level 2 [Member] Schedule of Fair Value of Separate Accounts by Major Category of Investment [Axis] Schedule of Fair Value of Separate Accounts by Major Category of Investment [Axis] Schedule of Fair Value of Separate Accounts by Major Category of Investment, Category [Domain] Schedule of Fair Value of Separate Accounts by Major Category of Investment, Category [Domain] Cash Equivalents Cash Equivalents [Member] Short-term Investments Short-term Investments [Member] Long-term Investments Long Term Investments [Member] Long Term Investments [Member] Restricted Cash and Cash Equivalents, Cash and Cash Equivalents [Axis] Restricted Cash and Cash Equivalents [Axis] Restricted Cash and Cash Equivalents, Cash and Cash Equivalents [Domain] Cash and Cash Equivalents [Domain] Corporate bonds Corporate Bond Securities [Member] Money market funds Money Market Funds [Member] Commercial paper Commercial Paper [Member] U.S. dollar dominated foreign corporate bonds Foreign Corporate Debt Securities [Member] Schedule of Available-for-sale Securities, Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Axis] Major Types of Debt and Equity Securities [Domain] Major Types of Debt and Equity Securities [Domain] U.S. government agency bonds Agency Securities [Member] Foreign bonds Foreign Government Debt Securities [Member] U.S. government treasury bonds US Treasury and Government [Member] Certificates of deposit Certificates of Deposit [Member] Municipal securities Municipal Securities [Member] Municipal Securities [Member] Israeli Severance Funds Israeli Severance Funds [Member] Israeli Severance Funds [Member] Asset-backed securities Asset-backed Securities [Member] Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Fair Value Assets And Liabilities Measured On Recurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring Basis [Line Items] Cash equivalents Cash and Cash Equivalents, Fair Value Disclosure Investments Available-for-sale Securities Other assets Other Assets, Fair Value Disclosure Assets, Fair Value Disclosure Assets, Fair Value Disclosure Goodwill and Intangible Assets Disclosure [Abstract] Schedule of Goodwill [Table] Schedule of Goodwill [Table] Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Cadent Holdings, Inc. [Member] Cadent Holdings, Inc. [Member] Cadent Holdings, Inc. [Member] ICA Holdings Pty Limited [Member] ICA Holdings Pty Limited [Member] ICA Holdings Pty Limited [Member] Business Segments [Axis] Segments [Axis] Segment [Domain] Segments [Domain] Clear Aligner [Member] Clear Aligner [Member] Clear Aligner [Member] Goodwill [Line Items] Goodwill [Line Items] Goodwill acquired Goodwill, Acquired During Period Short-Term And Long-Term Marketable Securities Available-for-sale Securities [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Investments Classified by Contractual Maturity Date [Table Text Block] Financial Assets Measured At Fair Value On Recurring Basis Fair Value, Assets Measured on Recurring Basis [Table Text Block] Schedule of Notional Amounts of Outstanding Derivative Positions Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Disclosure Stock Based Compensation Expense Related To All Stock Based Awards And Employee Stock Purchases [Abstract] Disclosure - Stock-Based Compensation Expense Related to All Stock-Based Awards and Employee Stock Purchases [Abstract] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Table] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line [Axis] Income Statement Location [Axis] Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Report Line [Domain] Income Statement Location [Domain] Cost of net revenues Cost of Sales [Member] Selling, general and administrative Selling and Marketing Expense [Member] Research and development Research and Development Expense [Member] Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items] Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items] Stock-based compensation expense Allocated Share-based Compensation Expense Statement of Comprehensive Income [Abstract] Net income Net change in cumulative translation adjustment Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Change in unrealized gains (losses) on available-for-sale securities, net of tax Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax Other comprehensive income (loss) Other Comprehensive Income (Loss), Net of Tax Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent Segments and Geographical Information Segment Reporting Disclosure [Text Block] Statement [Table] Statement [Table] Statement [Line Items] Statement [Line Items] Accounting for Income Taxes Income Tax Disclosure [Text Block] Net Profit Per Share Earnings Per Share [Text Block] Disclosure Accrued Liabilities [Abstract] Disclosure - Accrued Liabilities [Abstract] Accrued payroll and benefits Employee-related Liabilities, Current Accrued sales rebate Accrued Marketing Costs, Current Accrued sales tax and value added tax Sales and Excise Tax Payable, Current Accrued sales and marketing expenses Accrued Sales And Marketing Current Accrued Sales and Marketing, Current Accrued accounts payable Accrued Accounts Payable Accrued Accounts Payable Accrued warranty Standard Product Warranty Accrual, Current Accrued professional fees Accrued Professional Fees, Current Accrued income taxes Accrued Income Taxes, Current Other accrued liabilities Other Accrued Liabilities, Current Total Accrued Liabilities Disclosure Warranty Accrual Activity [Abstract] Disclosure - Warranty Accrual Activity [Abstract] Movement in Standard Product Warranty Accrual [Roll Forward] Movement in Standard Product Warranty Accrual [Roll Forward] Balance at beginning of period Standard Product Warranty Accrual Charged to cost of revenues Standard Product Warranty Accrual, Warranties Issued Actual warranty expenditures Standard Product Warranty Accrual, Payments Balance at end of period Schedule Of Earnings Per Share Basic And Diluted Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Disclosure Activity Under Stock Option Plans [Abstract] Disclosure - Activity Under Stock Option Plans [Abstract] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Number of Shares Underlying Stock Options Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Outstanding as of December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Cancelled or expired Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period Outstanding as of September 30, 2015 Vested and expected to vest at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Number Exercisable at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Weighted Average Exercise Price per Share Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Outstanding as of December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Exercised Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Cancelled or expired Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures and Expirations in Period, Weighted Average Exercise Price Outstanding as of September 30, 2015 Vested and expected to vest at June 30, 2014 (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Exercise Price Exercisable at June 30, 2014 (usd per share) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Weighted Average Remaining Contractual Term Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Remaining Contractual Term [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Term [Abstract] Outstanding as of September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Vested and expected to vest at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Weighted Average Remaining Contractual Term Exercisable at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Aggregate Intrinsic Value Share Based Compensation Arrangement By Share Based Payment Award Options Aggregate Intrinsic Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Aggregate Intrinsic Value [Abstract] Outstanding as of September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value Vested and expected to vest at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested and Expected to Vest, Outstanding, Aggregate Intrinsic Value Exercisable at September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Disclosure Common Stock Repurchase Program Additional Information [Abstract] Disclosure - Common Stock Repurchase Program - Additional Information [Abstract] Share Repurchases [Table] Share Repurchases [Table] Share Repurchases [Table] Share Repurchase Program [Axis] Share Repurchase Program [Axis] Share Repurchase Program [Domain] Share Repurchase Program [Domain] Accelerated Share Repurchase Program [Member] Accelerated Share Repurchase Program [Member] Accelerated Share Repurchase Program [Member] April 2014 Stock Repurchase Program [Member] April 2014 Stock Repurchase Program [Member] April 2014 Stock Repurchase Program [Member] Share Repurchases [Line Items] Share Repurchases [Line Items] Share Repurchases [Line Items] Repurchase of common stock, common stock authorized Stock Repurchase Program, Authorized Amount Stock repurchase program, period Stock Repurchase Program, Period in Force Stock repurchase program, authorized amount for next twelve months Stock Repurchase Program, Authorized Amount for Next Twelve Months Stock Repurchase Program, Authorized Amount for Next Twelve Months Accelerated share repurchase, contracted amount of repurchase Accelerated Share Repurchase, Contracted Amount of Repurchase Accelerated Share Repurchase, Contracted Amount of Repurchase Payments under accelerated share repurchase agreement Accelerated Share Repurchases, Settlement (Payment) or Receipt Treasury Stock, Shares, Acquired Treasury Stock, Shares, Acquired Share Repurchases Price Paid Per Share Share Repurchases Price Paid Per Share Share Repurchases, Price Paid Per Share Stock Repurchased During Period, Shares Stock Repurchased During Period, Shares Stock Repurchased During Period, Average Price Per Share Stock Repurchased During Period, Average Price Per Share Stock Repurchased During Period, Average Price Per Share Stock Repurchased During Period, Value Stock Repurchased During Period, Value Remaining authorized amount Stock Repurchase Program, Remaining Authorized Repurchase Amount Repurchases expected in next six months Stock Repurchase Program, Authorized Amount For Next Six Months Stock Repurchase Program, Authorized Amount For Next Six Months Schedule of Future Lease Payments Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block] Disclosure Summary Of M S U Performance [Abstract] Disclosure - Summary of MSU Performance [Abstract] Award Type [Axis] Award Type [Axis] Award Type [Domain] Equity Award [Domain] Market Performance Based Restricted Stock Units Market Performance Based Restricted Stock Units [Member] Market Performance Based Restricted Stock Units [Member] Number of Shares Underlying MSUs Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Nonvested as of December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Vested and released Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Nonvested as of September 30, 2015 Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Nonvested as of December 31, 2014 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Vested and released Sharebased Compensation Arrangement By Sharebased Payment Award Equity Instruments Other Than Options Vested And Released In Period Weighted Average Grant Date Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other Than Options Vested And Released In Period Weighted Average Grant Date Fair Value Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Nonvested as of September 30, 2015 Weighted Average Remaining Vesting Period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Nonvested as of September 30, 2015 Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Term 1 Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Outstanding Weighted Average Remaining Contractual Term 1 Aggregate Intrinsic Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value [Abstract] Nonvested as of September 30, 2015 Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Aggregate Intrinsic Value, Outstanding Disclosure Short Term And Long Term Marketable Securities [Abstract] Disclosure - Short-Term and Long-Term Marketable Securities [Abstract] Schedule of Available-for-sale Securities [Table] Schedule of Available-for-sale Securities [Table] Corporate bonds Corporate Bonds [Member] Corporate Bonds [Member] Foreign Government Debt Securities [Member] US Treasury Bond Securities [Member] US Treasury Bond Securities [Member] Schedule of Available-for-sale Securities [Line Items] Schedule of Available-for-sale Securities [Line Items] Amortized Cost Available-for-sale Securities, Amortized Cost Basis Gross Unrealized Gains Available For Sale Securities Gross Unrealized Gain In Investments Available For Sale Securities Gross Unrealized Gain In Investments Gross Unrealized Losses Available For Sale Securities Gross Unrealized Loss In Investments Available For Sale Securities Gross Unrealized Loss In Investments Total available for sale short-term and long-term marketable securities Legal Proceedings [Abstract] Legal Proceedings [Abstract] Legal Proceedings Legal Proceedings [Text Block] Legal Proceedings [Text Block] Disclosure Change In Carrying Value Of Goodwill [Abstract] Disclosure - Change in Carrying Value of Goodwill [Abstract] Goodwill [Roll Forward] Goodwill [Roll Forward] Balance as of December 31, 2014 Adjustments Goodwill, Translation and Purchase Accounting Adjustments Balance as of September 30, 2015 Disclosure Stockbased Compensation Additional Information [Abstract] Disclosure - Stock-based Compensation - Additional Information [Abstract] Employee Stock Purchase Plan 2010 Employee Stock Purchase Plan 2010 [Member] Employee Stock Purchase Plan, 2010 [Member] Restricted Stock Units (RSUs) Restricted Stock Units (RSUs) [Member] Employee Stock Purchase Plan Employee Stock Purchase Plan [Member] Employee Stock Purchase Plan [Member] Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Axis] Schedule Of Share Based Compensation Arrangement By Share Based Payment Award [Axis] Schedule of Share-based Compensation Arrangement by Share-based Payment Award [Axis] Share-based Compensation Arrangements by Share-based Payment Award [Domain] Share Based Compensation Arrangements By Share Based Payment Award [Domain] Share-based Compensation Arrangements by Share-based Payment Award [Domain] Incentive Plan 2005 Stock Incentive Plan 2005 [Member] 2005 Stock Incentive Plan [Member] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Shares reserved for issuance Common Stock, Capital Shares Reserved for Future Issuance Number of shares available for issuance Common Stock, Capital Shares Reserved For Future Issuance, Shares Available Common Stock, Capital Shares Reserved For Future Issuance, Shares Available Total unamortized compensation cost Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Weighted average period of total unamortized cost (in years) Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Vesting period of granted market-performance based restricted stock units Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Percentage of market-performance based restricted stock units eligible to vest over the vesting period Percentage Of Market Performance Based Restricted Stock Units During Vesting Period Maximum percentage of market-performance based restricted stock units during vesting period. Maximum number of shares available Employee Stock Purchase Plan Number Of Shares Available For Issuance Employee Stock Purchase Plan, Number Of Shares Available for Issuance Number of shares remaining Share Based Compensation Arrangement By Share Based Payment Award Shares Remaining Available For Issuance Share Based Compensation Arrangement By Share Based Payment Award Shares Remaining Available For Issuance Stock-based Compensation Expense Schedule of Compensation Cost for Share-based Payment Arrangements, Allocation of Share-based Compensation Costs by Plan [Table Text Block] Stock Option Activity Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Summary Of Nonvested Shares Schedule of Share-based Compensation, Restricted Stock Units Award Activity [Table Text Block] Summary Of Nonvested Shares Schedule of Nonvested Performance-based Units Activity [Table Text Block] Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block] Disclosure Intangible Assets As Direct Result From Cadent Acquisition [Abstract] Disclosure - Intangible Assets as Direct Result from Cadent Acquisition [Abstract] Schedule of Finite-Lived Intangible Assets by Major Class [Table] Schedule of Finite-Lived Intangible Assets [Table] Acquired Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Trademarks Trademarks [Member] Existing technology Existing Technology [Member] Existing Technology [Member] Customer relationships Customer Relationships [Member] Other Other Intangible Assets [Member] Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Weighted Average Amortization Period (in years) Acquired Finite-lived Intangible Assets, Weighted Average Useful Life Gross Carrying Amount, beginning balance Finite-Lived Intangible Assets, Gross Accumulated Amortization Finite Lived Intangible Assets Accumulated Amortization Period Increase Decrease Finite-Lived Intangible Assets, Accumulated Amortization, Period Increase (Decrease) Accumulated Impairment Loss Finite-Lived Intangible Assets, Accumulated Impairment Loss Finite-Lived Intangible Assets, Accumulated Impairment Loss Net Carrying Value, ending balance Finite-Lived Intangible Assets, Net Investments, Debt and Equity Securities [Abstract] Due in one year or less Available-for-sale Securities, Current Due in greater than one year Available-for-sale Securities, Noncurrent Basis of presentation Basis of Accounting, Policy [Policy Text Block] Use of estimates Use of Estimates, Policy [Policy Text Block] Recent Accounting Pronouncements Recent Accounting Pronouncements [Policy Text Block] Recent accounting pronouncements , Policy [Text Block] Document Documentand Entity Information [Abstract] Document and Entity Information [Abstract] Entities [Table] Entities [Table] Document Information [Line Items] Document Information [Line Items] Trading Symbol Trading Symbol Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Current Fiscal Year End Date Current Fiscal Year End Date Entity Filer Category Entity Filer Category Document Type Document Type Document Period End Date Document Period End Date Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Amendment Flag Amendment Flag Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Disclosure Total Estimated Annual Future Amortization Expense For Acquired Intangible Assets [Abstract] Disclosure - Total Estimated Annual Future Amortization Expense for Acquired Intangible Assets [Abstract] Remainder of 2015 Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year 2015 Finite-Lived Intangible Assets, Amortization Expense, Year Two 2016 Finite-Lived Intangible Assets, Amortization Expense, Year Three 2017 Finite-Lived Intangible Assets, Amortization Expense, Year Four 2018 Finite-Lived Intangible Assets, Amortization Expense, Year Five Thereafter Future Amortization Expense Thereafter Future Amortization Expense, Thereafter Major Types of Debt and Equity Securities [Axis] Maturity Period Used To Classify Investments Maturity Period Used To Classify Investments Maturity Period Used to Classify Investments Goodwill and Intangible Asset Impairment [Abstract] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Scanners and Services Scanners And Services [Member] Scanners and Services [Member] Accounts receivable, allowance for doubtful accounts and returns Allowance For Doubtful Accounts Receivable And Sales Returns Current Allowance For Doubtful Accounts Receivable And Sales Returns Current Preferred stock, par value (in usd per share) Preferred Stock, Par or Stated Value Per Share Preferred stock, shares authorized Preferred Stock, Shares Authorized Preferred stock, shares issued Preferred Stock, Shares Issued Common stock, par value (in usd per share) Common Stock, Par or Stated Value Per Share Common stock, shares authorized Common Stock, Shares Authorized Common stock, shares issued Common Stock, Shares, Issued Common stock, shares outstanding Common Stock, Shares, Outstanding Derivative [Table] Derivative [Table] Currency [Axis] Currency [Axis] All Currencies [Domain] All Currencies [Domain] US dollar United States of America, Dollars Euro Euro Member Countries, Euro Japanese yen Japan, Yen Australian dollar Australia, Dollars Hong Kong dollar Hong Kong, Dollars Singapore dollar Singapore, Dollars Fair Value Hierarchy [Domain] Prepaid Expenses and Other Current Assets Prepaid Expenses and Other Current Assets [Member] Derivative Instrument [Axis] Derivative Instrument [Axis] Derivative Contract [Domain] Derivative Contract [Domain] Foreign Exchange Forward Foreign Exchange Forward [Member] Derivative [Line Items] Derivative [Line Items] Decrease in fair value Derivative, Loss on Derivative Notional amount Derivative Asset, Notional Amount Credit Facilities Debt Disclosure [Text Block] Balance Sheet Components Supplemental Balance Sheet Disclosures [Text Block] Disclosure Accounting For Income Taxes Additional Information [Abstract] Disclosure - Accounting for Income Taxes - Additional Information [Abstract] Income Taxes [Table] Income Taxes [Table] Income Taxes [Table] Scenario [Axis] Scenario [Axis] Scenario, Unspecified [Domain] Scenario, Unspecified [Domain] Restatement Adjustment [Member] Restatement Adjustment [Member] Income Tax Authority [Axis] Income Tax Authority [Axis] Income Tax Authority [Domain] Income Tax Authority [Domain] Foreign Tax Authority [Member] Foreign Tax Authority [Member] Income Taxes [Line Items] Income Taxes [Line Items] Income Taxes [Line Items] Provision for income taxes Income Tax Expense (Benefit) Effective income tax rate, continuing operations Effective Income Tax Rate Reconciliation, Percent Statutory rate Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent Valuation allowance, deferred tax asset Deferred Tax Assets, Valuation Allowance Unrecognized tax benefits Unrecognized Tax Benefits Foreign income tax rate Effective Income Tax Reconciliation, at Foreign Income Tax Rate Effective Income Tax Reconciliation, at Foreign Income Tax Rate Tax Holiday effect Effective Income Tax Rate Reconciliation, Tax Holiday, Amount Tax holiday effect on diluted earnings per share Effective Income Tax Rate Reconciliation, Tax Holiday, Effect on Diluted Earnings Per Share Effective Income Tax Rate Reconciliation, Tax Holiday, Effect on Diluted Earnings Per Share Goodwill and Long-lived Assets Goodwill and Intangible Assets Disclosure [Text Block] Disclosure Balance Sheet Components Additional Information [Abstract] Disclosure - Balance Sheet Components - Additional Information [Abstract] Scanners, Warranty period Standard Product Warranty Time Period Standard Product Warranty Time Period Commitments and Contingencies Commitments and Contingencies Disclosure [Text Block] Summary of Goodwill by Reportable Segment Schedule of Goodwill [Table Text Block] Schedule Of Amortized Intangible Assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Schedule of Finite-Lived Intangible Assets, Future Amortization Expense Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block] Marketable Securities and Fair Value Measurements Financial Instruments Disclosure [Text Block] Disclosure Summary Of Nonvested Shares [Abstract] Disclosure - Summary of Nonvested Shares [Abstract] Number of Shares Underlying RSUs Weighted Average Grant Date Fair Value Weighted Remaining Vesting Period Income Statement [Abstract] Cost of net revenues Cost of Revenue Gross profit Gross Profit Operating expenses: Operating Expenses [Abstract] Selling, general and administrative Selling and Marketing Expense Research and development Research and Development Expense Total operating expenses Operating Expenses Income from operations Operating Income (Loss) Interest and other income (expenses), net Nonoperating Income (Expense) Net income before provision for income taxes Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest Net income Net income per share: Earnings Per Share [Abstract] Basic (in usd per share) Diluted (in usd per share) Shares used in computing net income per share: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Basic (in shares) Diluted (in shares) Business Combinations [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Business Acquisition [Line Items] Business Acquisition [Line Items] Schedule of Inventories Schedule of Inventory, Current [Table Text Block] Schedule of Accrued Liabilities Schedule of Accrued Liabilities [Table Text Block] Warranty Accrual Schedule of Product Warranty Liability [Table Text Block] Statement of Cash Flows [Abstract] CASH FLOWS FROM OPERATING ACTIVITIES: Net Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net profit to net cash provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Deferred taxes Deferred Income Tax Expense (Benefit) Depreciation and amortization Depreciation, Depletion and Amortization Stock-based compensation Share-based Compensation Excess tax benefit from share-based payment arrangements Excess Tax Benefit from Share-based Compensation, Operating Activities Other non-cash operating activities Other Noncash Income (Expense) Changes in assets and liabilities, net of acquired assets and liabilities: Increase (Decrease) in Operating Capital [Abstract] Accounts receivable Increase (Decrease) in Accounts Receivable Inventories Increase (Decrease) in Inventories Prepaid expenses and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accounts payable Increase (Decrease) in Accounts Payable Accrued and other long-term liabilities Increase (Decrease) in Accrued Liabilities and Other Operating Liabilities Deferred revenues Increase (Decrease) in Deferred Revenue Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities CASH FLOWS FROM INVESTING ACTIVITIES: Net Cash Provided by (Used in) Investing Activities [Abstract] Purchase of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Purchase of marketable securities Payments to Acquire Available-for-sale Securities Proceeds from maturities of marketable securities Proceeds from Sale and Maturity of Available-for-sale Securities Proceeds from sales of marketable securities Proceeds from Sale of Available-for-sale Securities Other investing activities Payments for (Proceeds from) Other Investing Activities Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities CASH FLOWS FROM FINANCING ACTIVITIES: Net Cash Provided by (Used in) Financing Activities [Abstract] Proceeds from issuance of common stock Proceeds from Issuance of Common Stock Common stock repurchases Payments for Repurchase of Common Stock Excess tax benefit from share-based payment arrangements Excess Tax Benefit from Share-based Compensation, Financing Activities Employees’ taxes paid upon the vesting of restricted stock units Payments Related to Tax Withholding for Share-based Compensation Net cash used in financing activities Net Cash Provided by (Used in) Financing Activities Effect of foreign exchange rate changes on cash and cash equivalents Effect of Exchange Rate on Cash and Cash Equivalents Net decrease in cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and cash equivalents, beginning of the period Cash and cash equivalents, end of the period Disclosure Segment Information [Abstract] Disclosure - Segment Information [Abstract] Invisalign Full [Member] Invisalign Full [Member] Invisalign Full [Member] Revenue Gross profit