Investments - Troubled Debt Restructuring (Details) $ in Millions	12 Months Ended
Dec. 31, 2021 loan	Dec. 31, 2020 USD ($) loan
Commercial Real Estate Portfolio Segment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Troubled debt restructuring, Number of Contracts	0
Troubled Debt Restructuring, Premodification \| $		$ 45
Commercial portfolio segment
Financing Receivable, Troubled Debt Restructuring [Line Items]
Troubled debt restructuring, Number of Contracts		8
Private Placement
Financing Receivable, Troubled Debt Restructuring [Line Items]
Troubled debt restructuring, Number of Contracts		0
Financing Receivable, Troubled Debt Restructuring, Subsequent Default, Number of Contracts	0	0

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953676-111524

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Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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