Investments (Contractholder-Directed Equity Securities and FVO Securities) (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	$ 8,999	$ 8,284
Contracted-Directed Equity Securities and FVO Securities, FV-NI, Unrealized Gains (Losses)	2,695	2,388
Contractholder-directed equity securities and fair value option securities, at estimated fair value	11,694	10,672
Unit-linked investments
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	8,031	7,398
Contracted-Directed Equity Securities and FVO Securities, FV-NI, Unrealized Gains (Losses)	1,935	1,699
Contractholder-directed equity securities and fair value option securities, at estimated fair value	9,966	9,097
FVO securities
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	968	886
Contracted-Directed Equity Securities and FVO Securities, FV-NI, Unrealized Gains (Losses)	760	689
Contractholder-directed equity securities and fair value option securities, at estimated fair value	$ 1,728	$ 1,575

Equity and Trading Securities, FV-NI, Unrealized Gains (Losses)

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Cost of investment in debt investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6B

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- Definition

Amount of investment in debt security measured at fair value with change in fair value recognized in net income (trading) and investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(4))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483467/210-10-45-1

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