Fair Value of Financial Instruments - Changes in Unrealized Gains (Losses) Within Level 3 Financial Instruments Carried at Fair Value and Still Held (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	$ 1,767	$ 1,030	$ (605)
Fair Value, Liability, Recurring Basis, Still Held, Unrealized Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration]	Realized gain (loss)	Realized gain (loss)	Realized gain (loss)
Trading securities
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	$ 0	$ 8	$ (81)
Equity securities
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	(2)	(16)	54
Mortgage loans on real estate
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	0	(8)	(20)
Derivative investments
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	(121)	1	2
MRBs
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	904	1,071	(359)
Other assets – LPR ceded derivative
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	(16)	(6)	(106)
Funds withheld reinsurance liabilities – reinsurance-related embedded derivatives
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	(59)	0	0
Indexed annuity ceded embedded derivatives
Fair Value Assets and Liabilities Measured on Recurring Basis Level 3 Activity [Line Items]
Changes in unrealized gains (losses) included in net income	$ 1,061	$ (20)	$ (95)

Fair Value Assets And Liabilities Measured On Recurring Basis Level 3 Activity [Line Items]

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- Definition

Amount of unrealized gain (loss) recognized in income from liability measured at fair value on recurring basis using unobservable input (level 3) and still held.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-3

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

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- Definition

Indicates line item in statement of income or comprehensive income that includes unrealized gain (loss) from liability measured at fair value using unobservable input (level 3) and still held.

+ References

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