Investments - Mortgage Loans (Details) - Commercial Real Estate - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Mortgage Loans on Real Estate [Line Items]
New mortgage loans	$ 63	$ 131
Mortgage loans fully repaid	187	234
Mortgage loans foreclosed	$ 0	$ 0

Pertains to amount of mortgage loans fully repaid.

No definition available.

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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.

+ Details

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- Definition

Amount of decrease in investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from foreclosure.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Footnote 6))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

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- Definition

Amount of increase in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate, from new investment.

+ References

+ Details

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- Details

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