0001097149-21-000054 | 10-Q | XBRL Viewer

Cover Page - shares	6 Months Ended
Cover Page - shares	Jun. 30, 2021	Jul. 30, 2021
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Transition Report	false
Entity File Number	000-32259
Entity Registrant Name	ALIGN TECHNOLOGY, INC.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	94-3267295
Entity Address, Address Line One	410 North Scottsdale Road, Suite 1300
Entity Address, City or Town	Tempe
Entity Address, State or Province	AZ
Entity Address, Postal Zip Code	85281
City Area Code	602
Local Phone Number	742-2000
Title of 12(b) Security	Common Stock, $0.0001 par value
Trading Symbol	ALGN
Security Exchange Name	NASDAQ
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Shell Company	false
Entity Central Index Key	0001097149
Current Fiscal Year End Date	--12-31
Document Period End Date	Jun. 30, 2021
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	Q2
Amendment Flag	false
Entity Common Stock, Shares Outstanding		79,011,543

Label	Element	Value
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	$ 4,328,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	10,751,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	4,179,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	0
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	19,258,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	4,328,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	10,751,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	4,179,000
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	0
Finite-Lived Intangible Assets, Accumulated Impairment Loss	algn_FiniteLivedIntangibleAssetsAccumulatedImpairmentLoss	$ 19,258,000
Patent Infringement, Number of Lawsuits	algn_PatentInfringementNumberofLawsuits	3
Proceeds From Litigation Settlement, Investing Activities	algn_ProceedsFromLitigationSettlementInvestingActivities	$ 43,403,000
Proceeds From Litigation Settlement, Investing Activities	algn_ProceedsFromLitigationSettlementInvestingActivities	0
Payments For Equity Forward Contracts Related To Accelerated Stock Repurchase Agreements	algn_PaymentsForEquityForwardContractsRelatedToAcceleratedStockRepurchaseAgreements	40,000,000
Payments For Equity Forward Contracts Related To Accelerated Stock Repurchase Agreements	algn_PaymentsForEquityForwardContractsRelatedToAcceleratedStockRepurchaseAgreements	0
Finite-Lived Intangible Assets, Net Including Accumulated Foreign Currency Translation Gain (Loss)	algn_FiniteLivedIntangibleAssetsNetIncludingAccumulatedForeignCurrencyTranslationGainLoss	117,721,000
Finite-Lived Intangible Assets, Net Including Accumulated Foreign Currency Translation Gain (Loss)	algn_FiniteLivedIntangibleAssetsNetIncludingAccumulatedForeignCurrencyTranslationGainLoss	130,072,000
Interest Income and Other Income (Expense), Net	algn_InterestIncomeAndOtherIncomeExpenseNet	(100,000)
Interest Income and Other Income (Expense), Net	algn_InterestIncomeAndOtherIncomeExpenseNet	(493,000)
Interest Income and Other Income (Expense), Net	algn_InterestIncomeAndOtherIncomeExpenseNet	36,075,000
Interest Income and Other Income (Expense), Net	algn_InterestIncomeAndOtherIncomeExpenseNet	(17,056,000)
Finite Lived Intangible Assets, Accumulated Foreign Currency Translation Gain (Loss)	algn_FiniteLivedIntangibleAssetsAccumulatedForeignCurrencyTranslationGainLoss	8,499,000
Finite Lived Intangible Assets, Accumulated Foreign Currency Translation Gain (Loss)	algn_FiniteLivedIntangibleAssetsAccumulatedForeignCurrencyTranslationGainLoss	$ 13,037,000

Balance Sheet Components Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Notes To Financial Statements [Abstract]
Accrued expenses	$ 52,608	$ 42,536
Accrued property, plant and equipment	$ 33,756	$ 27,692

Goodwill and Intangible Assets - Total Estimated Annual Future Amortization Expense for Acquired Intangible Assets (Details) $ in Thousands	Jun. 30, 2021 USD ($)
Disclosure Total Estimated Annual Future Amortization Expense For Acquired Intangible Assets [Abstract]
Thereafter	$ 48,069

Common Stock Repurchase Programs - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2021
Share Repurchases [Line Items]
Adjustment to additional paid-in capital for remaining contract value of ASRs	$ 40,000	$ 40,000

Accounting for Income Taxes - Additional Information (Details) $ in Thousands	6 Months Ended
	Jun. 30, 2020 USD ($)
Disclosure Accounting For Income Taxes Additional Information [Abstract]
One-time tax benefit from intra-entity transfer of certain assets	$ 1,493,500