Segments and Geographical Information - Non-Cash Expenses (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2026	Mar. 31, 2025
Segment Reporting Information [Line Items]
Stock-based compensation	$ 40,924	$ 44,997
Depreciation and amortization	56,548	39,148
Change in estimated useful life \| Specifically identified manufacturing assets
Segment Reporting Information [Line Items]
Depreciation	15,600
Operating Segments \| Clear Aligner
Segment Reporting Information [Line Items]
Stock-based compensation	5,949	5,818
Depreciation and amortization	37,638	18,904
Operating Segments \| Systems and Services
Segment Reporting Information [Line Items]
Stock-based compensation	377	403
Depreciation and amortization	10,534	8,469
Unallocated corporate expenses
Segment Reporting Information [Line Items]
Stock-based compensation	34,598	38,776
Depreciation and amortization	$ 8,376	$ 11,775

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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