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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Investments (Reconciliation Of Available-For-Sale Securities From Cost Basis To Fair Value) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Allowance for Credit Losses	$ 37	$ 21	$ 20	$ 19
Fair Value	104,170	99,465
Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	113,321	110,944
Gross Unrealized Gains	1,501	1,041
Gross Unrealized Losses	10,615	12,499
Allowance for Credit Losses	37	21
Fair Value	104,170	99,465
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Allowance for Credit Losses	26	9	16	17
Corporate Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	90,738	88,950
Gross Unrealized Gains	1,108	763
Gross Unrealized Losses	8,950	10,538
Allowance for Credit Losses	26	9
Fair Value	82,870	79,166
ABS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	12,200	11,791
Gross Unrealized Gains	41	37
Gross Unrealized Losses	784	925
Allowance for Credit Losses	4	4
Fair Value	11,453	10,899
U.S. Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	397	377
Gross Unrealized Gains	9	5
Gross Unrealized Losses	24	31
Fair Value	382	351
Foreign Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	329	339
Gross Unrealized Gains	19	17
Gross Unrealized Losses	43	45
Fair Value	305	311
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Allowance for Credit Losses	6	7	$ 2	$ 1
RMBS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	2,142	2,025
Gross Unrealized Gains	23	21
Gross Unrealized Losses	174	203
Allowance for Credit Losses	6	7
Fair Value	1,985	1,836
CMBS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	1,902	1,908
Gross Unrealized Gains	2	3
Gross Unrealized Losses	233	244
Fair Value	1,671	1,667
State And Municipal Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	5,259	5,198
Gross Unrealized Gains	274	170
Gross Unrealized Losses	380	483
Fair Value	5,153	4,885
Hybrid And Redeemable Preferred Securities [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	354	356
Gross Unrealized Gains	25	25
Gross Unrealized Losses	27	30
Allowance for Credit Losses	1	1
Fair Value	$ 351	$ 350