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Debt - Schedule of Convertible Senior Notes (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	May 19, 2020	May 15, 2020	Oct. 09, 2019	Sep. 09, 2019	Jul. 03, 2018	Dec. 12, 2016
Debt Instrument [Line Items]
Interest Expense	$ 35,000,000	$ 128,000,000	$ 138,000,000
Convertible Debt
Debt Instrument [Line Items]
Aggregate Principal Amount	1,672,000,000
Unamortized Debt Issuance Costs	12,000,000	353,000,000
Fair Value	1,664,000,000	2,451,000,000
Contractual Coupon Interest	27,000,000	30,000,000	34,000,000
Amortization of Debt Discount		89,000,000	97,000,000
Amortization of Debt Issuance Costs	5,000,000	4,000,000	5,000,000
Interest Expense	32,000,000	123,000,000	136,000,000
Convertible Debt \| 1.375% convertible senior notes due 2026
Debt Instrument [Line Items]
Aggregate Principal Amount	$ 499,000,000						$ 500,000,000
Stated Interest Rate	1.375%
Effective Interest Rate	1.57%
Unamortized Debt Issuance Costs	$ 4,000,000	130,000,000
Fair Value	504,000,000	781,000,000
Contractual Coupon Interest	7,000,000	7,000,000	7,000,000
Amortization of Debt Discount		22,000,000	20,000,000
Amortization of Debt Issuance Costs	0	1,000,000	0
Interest Expense	7,000,000	30,000,000	27,000,000
Convertible Debt \| 2.75% convertible senior notes due 2025
Debt Instrument [Line Items]
Aggregate Principal Amount	$ 565,000,000			$ 65,000,000	$ 500,000,000
Stated Interest Rate	2.75%			2.75%	2.75%
Effective Interest Rate	3.20%
Unamortized Debt Issuance Costs	$ 5,000,000	122,000,000
Fair Value	531,000,000	725,000,000
Contractual Coupon Interest	16,000,000	16,000,000	10,000,000
Amortization of Debt Discount		27,000,000	15,000,000
Amortization of Debt Issuance Costs	3,000,000	1,000,000	1,000,000
Interest Expense	19,000,000	44,000,000	26,000,000
Convertible Debt \| 0.75% convertible senior notes due 2024
Debt Instrument [Line Items]
Aggregate Principal Amount	$ 608,000,000					$ 73,000,000	$ 600,000,000
Stated Interest Rate	0.75%					0.75%
Effective Interest Rate	1.02%
Unamortized Debt Issuance Costs	$ 3,000,000	101,000,000
Fair Value	629,000,000	945,000,000
Contractual Coupon Interest	4,000,000	4,000,000	5,000,000
Amortization of Debt Discount		32,000,000	33,000,000
Amortization of Debt Issuance Costs	2,000,000	1,000,000	1,000,000
Interest Expense	6,000,000	37,000,000	39,000,000
Convertible Debt \| 1.50% convertible senior notes due 2023
Debt Instrument [Line Items]
Aggregate Principal Amount								$ 374,000,000
Contractual Coupon Interest	0	3,000,000	6,000,000
Amortization of Debt Discount		8,000,000	15,000,000
Amortization of Debt Issuance Costs	0	1,000,000	1,000,000
Interest Expense	0	12,000,000	22,000,000
Convertible Debt \| Convertible Senior Notes due 2021, 2.0%
Debt Instrument [Line Items]
Aggregate Principal Amount									$ 460,000,000
Stated Interest Rate									2.00%
Contractual Coupon Interest	0	0	6,000,000
Amortization of Debt Discount		0	14,000,000
Amortization of Debt Issuance Costs	0	0	2,000,000
Interest Expense	$ 0	$ 0	$ 22,000,000