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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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Amortized cost, after allowance for credit loss, 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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Investments (Reconciliation Of Available-For-Sale Securities From Cost Basis To Fair Value) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	$ 110,944	$ 110,323	$ 108,963	$ 106,939	$ 104,491	$ 106,752	$ 105,530	$ 104,684
Gross Unrealized Gains	1,041				13,431
Gross Unrealized Losses	12,499				427
Allowance for Credit Losses	21	18	12	20	19	17	9	14	$ 13
Fair Value	99,465	$ 97,391	$ 102,954	$ 109,889	117,476	$ 120,794	$ 120,452	$ 115,695
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	88,950				86,197
Gross Unrealized Gains	763				11,569
Gross Unrealized Losses	10,538				326
Allowance for Credit Losses	9				17				12
Fair Value	79,166				97,423
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	11,791				8,433
Gross Unrealized Gains	37				127
Gross Unrealized Losses	925				54
Allowance for Credit Losses	4
Fair Value	10,899				8,506
U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	377				348
Gross Unrealized Gains	5				54
Gross Unrealized Losses	31				2
Fair Value	351				400
Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	339				365
Gross Unrealized Gains	17				63
Gross Unrealized Losses	45				5
Fair Value	311				423
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	2,025				2,132
Gross Unrealized Gains	21				178
Gross Unrealized Losses	203				4
Allowance for Credit Losses	7				1				$ 1
Fair Value	1,836				2,305
CMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	1,908				1,542
Gross Unrealized Gains	3				62
Gross Unrealized Losses	244				14
Fair Value	1,667				1,590
State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	5,198				5,113
Gross Unrealized Gains	170				1,275
Gross Unrealized Losses	483				11
Fair Value	4,885				6,377
Hybrid And Redeemable Preferred Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost	356				361
Gross Unrealized Gains	25				103
Gross Unrealized Losses	30				11
Allowance for Credit Losses	1				1
Fair Value	$ 350				$ 452