Goodwill and Intangible Assets - Change in Carrying Value of Goodwill (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2021	$ 418,547
Foreign currency translation adjustments	(6,582)
Balance as of March 31, 2022	411,965
Clear Aligner
Goodwill [Roll Forward]
Balance as of December 31, 2021	112,208
Foreign currency translation adjustments	(642)
Balance as of March 31, 2022	111,566
Systems and Services
Goodwill [Roll Forward]
Balance as of December 31, 2021	306,339
Foreign currency translation adjustments	(5,940)
Balance as of March 31, 2022	$ 300,399