Income Taxes Income Taxes - Effective Tax Rates Differing From Prevailing Federal Corporate Income Tax Rates (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Reconciliation of Effective Tax Rates [Line Items]
Tax on income from continuing operations at statutory rate	$ 3	$ 110	$ 0
Tax on income from continuing operations at statutory rate,tax rate	21.00%	21.00%	21.00%
Tax-exempt interest	$ 0	$ (1)	$ (2)
Tax-exempt interest, tax rate	0.00%	0.00%	(114.00%)
Derivative, Gain (Loss) on Derivative, Net	$ (1)	$ 129	$ 22
Valuation allowance	$ 2	$ (131)	$ (4)
Valuation allowance, tax rate	13.00%	(25.00%)	(230.00%)
Other, net	$ 4	$ (4)	$ 1
Foreign taxes	$ 9	$ 4	$ 8
Foreign taxes, tax rate	70.00%	1.00%	448.00%
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Amount	$ 0	$ (1)	$ 14
Effective Income Tax Rate Reconciliation, State and Local Income Taxes, Percent	(1.00%)	0.00%	794.00%
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Percent	118.00%	0.00%	0.00%
Effective Income Tax Rate Reconciliation, Prior Year Income Taxes, Amount	$ 15	$ 0	$ 0
Other, net, tax rate	35.00%	(1.00%)	72.00%
Income tax expense (benefit)	$ 7	$ 2	$ 18
Effective Income Tax Rate Reconciliation, Percent	60.00%	1.00%	991.00%
Effective Tax Rate Reconciliation, Variable Interest Entities	$ (24)	$ 25
Effective Tax Rate Reconciliation, Variable Interest Entities, Percent	(197.00%)	5.00%
Futures Contracts [Member]
Reconciliation of Effective Tax Rates [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ 0	$ 62	$ 9
Interest Rate Swaps [Member]
Reconciliation of Effective Tax Rates [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(1)	65	13
Variable Interest Entity, Primary Beneficiary [Member]
Reconciliation of Effective Tax Rates [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(63)	565	(150)
Variable Interest Entity, Primary Beneficiary [Member] \| Currency Swaps [Member]
Reconciliation of Effective Tax Rates [Line Items]
Derivative, Gain (Loss) on Derivative, Net	(1)	24	2
Variable Interest Entity, Primary Beneficiary [Member] \| Interest Rate Swaps [Member]
Reconciliation of Effective Tax Rates [Line Items]
Derivative, Gain (Loss) on Derivative, Net	$ (62)	$ 541	$ (152)

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