Derivative Instruments - Schedule of Activity Associated with Derivative Instruments (Details) $ in Millions	3 Months Ended
Mar. 31, 2026 USD ($) policy
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	$ 13,691
Additions	1,971
Maturities/ terminations	(2,329)
Notional amount, ending balance	13,333
Derivatives designated as hedges
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	11,178
Additions	106
Maturities/ terminations	(324)
Notional amount, ending balance	10,960
Derivatives designated as hedges \| Cash flow hedges
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	11,178
Additions	106
Maturities/ terminations	(324)
Notional amount, ending balance	10,960
Derivatives designated as hedges \| Cash flow hedges \| Interest rate swaps
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	8,058
Additions	0
Maturities/ terminations	(324)
Notional amount, ending balance	7,734
Derivatives designated as hedges \| Cash flow hedges \| Foreign currency swaps
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	156
Additions	0
Maturities/ terminations	0
Notional amount, ending balance	156
Derivatives designated as hedges \| Forward bond purchase commitments \| Cash flow hedges
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	2,964
Additions	106
Maturities/ terminations	0
Notional amount, ending balance	3,070
Derivatives not designated as hedges
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	2,513
Additions	1,865
Maturities/ terminations	(2,005)
Notional amount, ending balance	2,373
Derivatives not designated as hedges \| Equity index options
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	503
Additions	110
Maturities/ terminations	(145)
Notional amount, ending balance	468
Derivatives not designated as hedges \| Financial futures
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	989
Additions	1,236
Maturities/ terminations	(1,339)
Notional amount, ending balance	886
Derivatives not designated as hedges \| Foreign currency forward contracts
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	521
Additions	519
Maturities/ terminations	(521)
Notional amount, ending balance	519
Derivatives not designated as hedges \| Forward bond purchase commitments
Derivative, Notional Amount [Roll Forward]
Notional amount, beginning balance	500
Additions	0
Maturities/ terminations	0
Notional amount, ending balance	$ 500
Derivatives not designated as hedges \| Fixed indexed annuity embedded derivatives
Number Of Policies [Roll Forward]
Notional amount, beginning balance \| policy	4,171
Additions \| policy	0
Maturities/ terminations \| policy	(169)
Notional amount, ending balance \| policy	4,002
Derivatives not designated as hedges \| Indexed universal life embedded derivatives
Number Of Policies [Roll Forward]
Notional amount, beginning balance \| policy	688
Additions \| policy	0
Maturities/ terminations \| policy	0
Notional amount, ending balance \| policy	688

Derivative, Notional Amount

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Additions during period to notional amount of derivatives.

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+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 181
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480401/815-10-55-181

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1B

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1A
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-1A

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