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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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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	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Jun. 30, 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	$ 109,019		$ 104,526
Gross Unrealized Gains	2,213		13,431
Gross Unrealized Losses	8,218		427
Allowance for Credit Losses	12	$ 20	19	$ 9	$ 14	$ 13
Fair Value	103,002		117,511
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	88,629		86,197
Gross Unrealized Gains	1,596		11,569
Gross Unrealized Losses	6,970		326
Allowance for Credit Losses	7	16	17	8	13	12
Fair Value	83,248		97,423
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	10,268		8,433
Gross Unrealized Gains	47		127
Gross Unrealized Losses	609		54
Allowance for Credit Losses	1
Fair Value	9,705		8,506
U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	387		348
Gross Unrealized Gains	13		54
Gross Unrealized Losses	14		2
Fair Value	386		400
Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	353		365
Gross Unrealized Gains	25		63
Gross Unrealized Losses	38		5
Fair Value	340		423
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	2,047		2,132
Gross Unrealized Gains	48		178
Gross Unrealized Losses	100		4
Allowance for Credit Losses	3	$ 2	1	$ 1	$ 1	$ 1
Fair Value	1,992		2,305
CMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	1,698		1,542
Gross Unrealized Gains	2		62
Gross Unrealized Losses	151		14
Fair Value	1,549		1,590
State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Available-for-sale Securities, Debt Maturities, Amortized Cost Basis, Total	5,214		5,113
Gross Unrealized Gains	413		1,275
Gross Unrealized Losses	301		11
Fair Value	5,326		6,377
Hybrid And Redeemable Preferred 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	423		396
Gross Unrealized Gains	69		103
Gross Unrealized Losses	35		11
Allowance for Credit Losses	1		1
Fair Value	$ 456		$ 487