Investments - Schedule of Consolidated Investments (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Available-for-sale securities
Amortized Cost	$ 57,703	$ 57,161
Allowance for Expected Credit Losses	(91)	(112)
Gross Unrealized Gains	378	622
Gross Unrealized Losses	(3,583)	(3,110)
Fair Value	54,407	54,561
Asset-backed securities
Available-for-sale securities
Amortized Cost	18,868	18,853
Allowance for Expected Credit Losses	(20)	(25)
Gross Unrealized Gains	119	166
Gross Unrealized Losses	(362)	(256)
Fair Value	18,605	18,738
Commercial mortgage-backed securities
Available-for-sale securities
Amortized Cost	5,179	5,341
Allowance for Expected Credit Losses	(63)	(61)
Gross Unrealized Gains	35	58
Gross Unrealized Losses	(154)	(139)
Fair Value	4,997	5,199
Corporates
Available-for-sale securities
Amortized Cost	27,372	26,538
Allowance for Expected Credit Losses	(7)	(25)
Gross Unrealized Gains	155	302
Gross Unrealized Losses	(2,694)	(2,368)
Fair Value	24,826	24,447
Hybrids
Available-for-sale securities
Amortized Cost	643	625
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	3	6
Gross Unrealized Losses	(27)	(22)
Fair Value	619	609
Municipals
Available-for-sale securities
Amortized Cost	1,587	1,604
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	3	4
Gross Unrealized Losses	(223)	(215)
Fair Value	1,367	1,393
Residential mortgage-backed securities
Available-for-sale securities
Amortized Cost	2,672	2,846
Allowance for Expected Credit Losses	(1)	(1)
Gross Unrealized Gains	59	76
Gross Unrealized Losses	(72)	(70)
Fair Value	2,658	2,851
U.S. Government
Available-for-sale securities
Amortized Cost	967	954
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	3	5
Gross Unrealized Losses	(5)	(3)
Fair Value	965	956
Foreign Governments
Available-for-sale securities
Amortized Cost	415	400
Allowance for Expected Credit Losses	0	0
Gross Unrealized Gains	1	5
Gross Unrealized Losses	(46)	(37)
Fair Value	$ 370	$ 368

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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
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