Equity (Schedule of Reclassifications out of AOCI) (Details) - USD ($) $ in Millions		3 Months Ended		12 Months Ended
		Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022	Dec. 31, 2021
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Income Tax Expense (Benefit)		$ (98)	$ (70)
Net income		252	197	$ 517	$ 1,170
Unrealized Appreciation Depreciation Of Investments [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Investment related gains (losses), net		(87)	(35)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest		(88)	(36)
Income Tax Expense (Benefit)		18	7
Net income		(70)	(29)
Amortization Of Unrealized Pension And Postretirement Benefits [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Prior service cost	[1]	0	0
Actuarial gains/(losses)	[1]	(1)	(1)
Income (Loss) from Continuing Operations before Equity Method Investments, Income Taxes, Noncontrolling Interest		(1)	(1)
Income Tax Expense (Benefit)		0	0
Net income		(1)	(1)
Amounts Reclassified From AOCI [Member]
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Net income		(71)	(30)
Currency Swap [Member] | Unrealized Appreciation Depreciation Of Investments [Member] | Unrealized Gains Losses On Available For Sale Securities [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]	(3)	(1)
Interest Rate Options [Member] | Unrealized Appreciation Depreciation Of Investments [Member] | Unrealized Gains Losses On Available For Sale Securities [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]	$ 2	$ 0

[1] This AOCI component is included in the computation of the net periodic pension cost. See Note 15 – “Employee Benefit Plans” for additional details.

[2] See Note 12 – “Derivative Instruments” for additional information on cash flow hedges.