Changes in and Reclassifications From Accumulated Other Comprehensive Income (Loss) - Reclassification from AOCI (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net realized gains (losses)									$ (188)	$ (627)	$ 509
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									3,088	2,262	2,905
Income tax expense									584	443	534
Net investment income									2,305	2,177	2,313
Interest Expense									199	213	234
Net income (loss)	$ 771	$ 651	$ 547	$ 535	$ 592	$ 340	$ 444	$ 443	2,504	1,819	2,371
Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net income (loss)									(136)	(262)	158
Net Unrealized Gain (Loss) on Fixed Maturities, AFS | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net realized gains (losses)									(133)	(282)	234
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									(133)	(282)	234
Income tax expense									(28)	(59)	49
Net income (loss)									(105)	(223)	185
AOCI, Gain (Loss), Debt Securities, Available-for-sale, with Allowance for Credit Loss, Parent | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net realized gains (losses)									(4)	0	0
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									(4)	0	0
Income tax expense									(1)	0	0
Net income (loss)									(3)	0	0
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									(1)	13	36
Income tax expense									0	3	8
Net income (loss)									(1)	10	28
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Amount Reclassified from AOCI | Interest rate swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net investment income									(26)	6	41
Interest Expense									15	(2)	(10)
Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Amount Reclassified from AOCI | Foreign currency swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
Net investment income									10	9	5
Amortization of prior service credit | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Insurance operating costs and other expenses									7	7	7
Amortization of actuarial loss | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Insurance operating costs and other expenses									(34)	(69)	(77)
Pension and Other Postretirement Plan Adjustments | Amount Reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest									(27)	(62)	(70)
Income tax expense									0	(13)	(15)
Net income (loss)									$ (27)	$ (49)	$ (55)