Investments (Contractholder-Directed Equity Securities and FVO Securities) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	$ 9,886	$ 11,339
Debt Securities, Trading and Equity Securities, FV-NI, Unrealized Gains (Losses)	2,256	1,980
Contractholder-directed equity securities and fair value option securities, at estimated fair value	12,142	13,319
Unit-linked investments
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	8,643	9,934
Debt Securities, Trading and Equity Securities, FV-NI, Unrealized Gains (Losses)	1,897	1,774
Contractholder-directed equity securities and fair value option securities, at estimated fair value	10,540	11,708
FVO Securities
Debt and Equity Securities, FV-NI [Line Items]
Debt Securities, Trading, and Equity Securities, FV-NI, Cost	1,243	1,405
Debt Securities, Trading and Equity Securities, FV-NI, Unrealized Gains (Losses)	359	206
Contractholder-directed equity securities and fair value option securities, at estimated fair value	$ 1,602	$ 1,611

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

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- Definition

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

No definition available.

+ Details

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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

No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.4)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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