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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, 2022	Dec. 31, 2021	Mar. 31, 2021	Dec. 31, 2020
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	$ 106,974	$ 104,526
Allowance for Credit Losses	20	19	$ 14	$ 13
Fair Value	109,921	117,511
Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	106,974	104,526
Gross Unrealized Gains	5,855	13,431
Gross Unrealized Losses	2,888	427
Allowance for Credit Losses	20	19
Fair Value	109,921	117,511
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Allowance for Credit Losses	16	17	13	12
Corporate Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	87,914	86,197
Gross Unrealized Gains	4,778	11,569
Gross Unrealized Losses	2,400	326
Allowance for Credit Losses	16	17
Fair Value	90,276	97,423
ABS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	9,040	8,433
Gross Unrealized Gains	73	127
Gross Unrealized Losses	189	54
Allowance for Credit Losses	1
Fair Value	8,923	8,506
U.S. Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	364	348
Gross Unrealized Gains	29	54
Gross Unrealized Losses	5	2
Fair Value	388	400
Foreign Government Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	349	365
Gross Unrealized Gains	42	63
Gross Unrealized Losses	17	5
Fair Value	374	423
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Allowance for Credit Losses	2	1	$ 1	$ 1
RMBS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	2,092	2,132
Gross Unrealized Gains	85	178
Gross Unrealized Losses	40	4
Allowance for Credit Losses	2	1
Fair Value	2,135	2,305
CMBS [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	1,647	1,542
Gross Unrealized Gains	8	62
Gross Unrealized Losses	71	14
Fair Value	1,584	1,590
State And Municipal Bonds [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	5,171	5,113
Gross Unrealized Gains	758	1,275
Gross Unrealized Losses	145	11
Fair Value	5,784	6,377
Hybrid And Redeemable Preferred Securities [Member] \| Fixed Maturity AFS Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	397	396
Gross Unrealized Gains	82	103
Gross Unrealized Losses	21	11
Allowance for Credit Losses	1	1
Fair Value	$ 457	$ 487