Goodwill and Intangible Assets - Change in Carrying Value of Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2023 USD ($)
Goodwill [Roll Forward]
Balance as of December 31, 2022	$ 407,551
Foreign currency translation adjustments	(3,256)
Balance as of September 30, 2023	404,295
Clear Aligner
Goodwill [Roll Forward]
Balance as of December 31, 2022	109,480
Foreign currency translation adjustments	(479)
Balance as of September 30, 2023	109,001
Systems and Services
Goodwill [Roll Forward]
Balance as of December 31, 2022	298,071
Foreign currency translation adjustments	(2,777)
Balance as of September 30, 2023	$ 295,294