Financing Activities - Schedule of Extinguishment of Debt (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022	May 01, 2020
Debt Instrument [Line Items]
Cash payment	$ 209	$ 474
Principal repayment	168	362
Loss on partial extinguishment of convertible and unsecured notes	43	116
Non-cash amortization of debt discount and (issuance) costs	$ (2)	$ (4)
Convertible Debt
Debt Instrument [Line Items]
Stated interest rate			1.25%
1.25% Convertible Notes due 2025 \| Convertible Debt
Debt Instrument [Line Items]
Stated interest rate	1.25%	1.25%
Cash payment	$ 178	$ 409
Principal repayment	138	302
Loss on partial extinguishment of convertible and unsecured notes	42	112
Non-cash amortization of debt discount and (issuance) costs	$ (2)	$ (5)
5.125% Notes due 2027 \| Unsecured Debt
Debt Instrument [Line Items]
Stated interest rate	5.125%	5.125%
Cash payment	$ 27	$ 61
Principal repayment	26	56
Loss on partial extinguishment of convertible and unsecured notes	1	4
Non-cash amortization of debt discount and (issuance) costs	$ 0	$ 1
4.75% Notes due 2023 \| Unsecured Debt
Debt Instrument [Line Items]
Stated interest rate	4.75%	4.75%
Cash payment	$ 3	$ 3
Principal repayment	3	3
Loss on partial extinguishment of convertible and unsecured notes	0	0
Non-cash amortization of debt discount and (issuance) costs	$ 0	$ 0
5.25% Notes due 2025 \| Unsecured Debt
Debt Instrument [Line Items]
Stated interest rate	5.25%	5.25%
Cash payment	$ 1	$ 1
Principal repayment	1	1
Loss on partial extinguishment of convertible and unsecured notes	0	0
Non-cash amortization of debt discount and (issuance) costs	$ 0	$ 0

Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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