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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	Sep. 30, 2023	Jun. 30, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	$ 110,943		$ 110,944
Gross Unrealized Gains	590		1,041
Gross Unrealized Losses	11,125		12,499
Allowance for Credit Losses	21	$ 25	21	$ 18	$ 12	$ 19
Fair Value	100,387		99,465
Corporate Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	87,724		88,950
Gross Unrealized Gains	433		763
Gross Unrealized Losses	9,387		10,538
Allowance for Credit Losses	9	13	9	7	7	17
Fair Value	78,761		79,166
ABS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	13,177		11,791
Gross Unrealized Gains	36		37
Gross Unrealized Losses	820		925
Allowance for Credit Losses	5		4
Fair Value	12,388		10,899
U.S. Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	417		377
Gross Unrealized Gains	2		5
Gross Unrealized Losses	47		31
Fair Value	372		351
Foreign Government Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	321		339
Gross Unrealized Gains	10		17
Gross Unrealized Losses	61		45
Fair Value	270		311
RMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	2,067		2,025
Gross Unrealized Gains	18		21
Gross Unrealized Losses	210		203
Allowance for Credit Losses	6	$ 6	7	$ 5	$ 3	$ 1
Fair Value	1,869		1,836
CMBS [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	1,937		1,908
Gross Unrealized Gains			3
Gross Unrealized Losses	236		244
Fair Value	1,701		1,667
State And Municipal Bonds [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	4,950		5,198
Gross Unrealized Gains	67		170
Gross Unrealized Losses	346		483
Fair Value	4,671		4,885
Hybrid And Redeemable Preferred Securities [Member]
Amortized cost, gross unrealized gains, losses, OTTI and fair value of AFS securities
Amortized Cost, Total	350		356
Gross Unrealized Gains	24		25
Gross Unrealized Losses	18		30
Allowance for Credit Losses	1		1
Fair Value	$ 355		$ 350