Equity (Schedule of Reclassifications out of 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
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other investment related gains (losses), net										$ 24	$ 26	$ 25
Net investment income										3,591	3,161	3,138
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax										1	3	(2)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax										3	(33)	(27)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest		$ 164	$ 380	$ 265	$ 351	$ 381	$ (77)	$ 147	$ 267	1,160	718	1,385
Income Tax Expense (Benefit)										(251)	(197)	(215)
Net Income (Loss) Attributable to Parent										902	517	$ 1,170
Amortization Of Unrealized Pension And Postretirement Benefits [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other Comprehensive (Income) Loss, Defined Benefit Plan, Prior Service Cost (Credit), Reclassification Adjustment from AOCI, before Tax	[1]									2	(2)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax	[1]									(2)	(4)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest										0	(2)
Income Tax Expense (Benefit)										0	0
Net Income (Loss) Attributable to Parent										0	(2)
Unrealized Appreciation Depreciation Of Investments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other investment related gains (losses), net										(228)	(218)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Extraordinary Items, Noncontrolling Interest										(241)	(227)
Income Tax Expense (Benefit)										52	42
Net Income (Loss) Attributable to Parent										(189)	(185)
Amounts Reclassified From AOCI [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net Income (Loss) Attributable to Parent										(189)	(187)
Interest Rate Options [Member] | Unrealized Gains Losses On Available For Sale Securities [Member] | Unrealized Appreciation Depreciation Of Investments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	[2]									10	(1)
Currency Swap [Member] | Unrealized Gains Losses On Available For Sale Securities [Member] | Unrealized Appreciation Depreciation Of Investments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	[2]									$ (23)	$ (8)

[1] See Note 15 for information on employee benefit plans.

[2] See Note 12 for information on cash flow hedges.