Derivatives - Cash Flow Hedges (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Investment Income	$ 597	$ 487	$ 1,652	$ 1,537
Interest Expense	50	50	150	163
Interest rate swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Investment Income	(5)	(1)	(20)	13
Interest Expense	4	0	11	(4)
Foreign currency swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Investment Income	2	3	7	7
Cash Flow Hedging | Designated as Hedging Instrument
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	(5)	51	(19)	95
Cash Flow Hedging | Designated as Hedging Instrument | Reclassification out of Accumulated Other Comprehensive Income | Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(3)	2	(13)	20
Cash Flow Hedging | Designated as Hedging Instrument | Reclassification out of Accumulated Other Comprehensive Income | Interest expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	4	0	11	(4)
Cash Flow Hedging | Designated as Hedging Instrument | Interest rate swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	(8)	8	(12)	2
Cash Flow Hedging | Designated as Hedging Instrument | Interest rate swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	(5)	(1)	(20)	13
Cash Flow Hedging | Designated as Hedging Instrument | Interest rate swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	4	0	11	(4)
Cash Flow Hedging | Designated as Hedging Instrument | Foreign currency swaps
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), before Reclassification and Tax	3	43	(7)	93
Cash Flow Hedging | Designated as Hedging Instrument | Foreign currency swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Net investment income
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	2	3	7	7
Cash Flow Hedging | Designated as Hedging Instrument | Foreign currency swaps | Reclassification out of Accumulated Other Comprehensive Income | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Interest expense
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Gain (Loss) Reclassified from AOCI into Income (Effective Portion)	$ 0	$ 0	$ 0	$ 0