Reinsurance (Related Party Reinsurance - Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Effects of Reinsurance [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	$ 8,800	$ 7,584
Deposit Contracts, Assets	3,100	3,000
Deposit Contracts, Liabilities	3,400	2,700
Affiliated Entity
Effects of Reinsurance [Line Items]
Deposit Contracts, Assets	0
Deposit Contracts, Liabilities	157	167
New England Life Insurance Company [Member] \| Assumed guaranteed minimum benefits \| Affiliated Entity
Effects of Reinsurance [Line Items]
Embedded Derivative, Fair Value of Embedded Derivative Liability	427	596
Net derivatives gains (losses)	$ 172	$ (151)	$ (53)

Carrying amount of assets as of the balance sheet date pertaining to amounts paid by the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99397363&loc=d3e9420-108338

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99383045&loc=d3e9351-108337

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Carrying amount of liabilities as of the balance sheet date pertaining to amounts received by the insurer or reinsurer from the insured (including a ceding company) under insurance or reinsurance contracts for which insurance risk is not transferred.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99383045&loc=d3e9351-108337

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 340
-SubTopic 30
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99397363&loc=d3e9420-108338

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+ References

No definition available.

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Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=125515794&loc=SL5624163-113959

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Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 15
-URI http://asc.fasb.org/subtopic&trid=2229187

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