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Debt - Schedule of Carrying Value of Debt (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021	May 19, 2020	May 15, 2020	Oct. 09, 2019
Debt Instrument [Line Items]
Total debt	$ 1,697	$ 1,432
Convertible Debt
Debt Instrument [Line Items]
Total convertible senior notes	1,660	1,319
Convertible Debt \| 1.375% convertible senior notes due 2026
Debt Instrument [Line Items]
Total convertible senior notes	$ 495	369
Stated Interest Rate	1.375%
Convertible Debt \| 2.75% convertible senior notes due 2025
Debt Instrument [Line Items]
Total convertible senior notes	$ 560	443
Stated Interest Rate	2.75%		2.75%	2.75%
Convertible Debt \| 0.75% convertible senior notes due 2024
Debt Instrument [Line Items]
Total convertible senior notes	$ 605	507
Stated Interest Rate	0.75%				0.75%
Mortgages
Debt Instrument [Line Items]
Warehouse lines of credit	$ 37	113
Credit Suisse AG, Cayman Islands \| Mortgages
Debt Instrument [Line Items]
Repurchase agreements	23	77
Citibank, N.A. \| Mortgages
Debt Instrument [Line Items]
Repurchase agreements	3	17
Comerica Bank \| Line of Credit \| Mortgages
Debt Instrument [Line Items]
Warehouse lines of credit	$ 11	$ 19