Debt and Equity - Purchase of Senior Notes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Gain	$ 5	$ 20	$ 10	$ 28
Senior Notes
Debt Instrument [Line Items]
Principal Amount	233		233
Discounts/Deferred Issuance Costs	2		2
Book Value			231
Redemption Value	221		221
Gain			10
5.00% Senior Notes due March 2027 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	17		17
Discounts/Deferred Issuance Costs	0		0
Book Value			17
Redemption Value	17		17
Gain			0
4.125% Senior Notes Due 2028 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	61		61
Discounts/Deferred Issuance Costs	0		0
Book Value			61
Redemption Value	58		58
Gain			3
4.375% Senior Notes Due 2028 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	46		46
Discounts/Deferred Issuance Costs	1		1
Book Value			45
Redemption Value	43		43
Gain			2
5.25% Senior Notes Due 2029 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	31		31
Discounts/Deferred Issuance Costs	0		0
Book Value			31
Redemption Value	31		31
Gain			0
4.25% Senior Notes Due 2030 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	50		50
Discounts/Deferred Issuance Costs	1		1
Book Value			49
Redemption Value	46		46
Gain			3
4.625% Senior Notes Due 2030 | Senior Notes
Debt Instrument [Line Items]
Principal Amount	28		28
Discounts/Deferred Issuance Costs	0		0
Book Value			28
Redemption Value	$ 26		26
Gain			$ 2