Investments - Schedule of Commercial Mortgage Loan Investment (Details) $ in Millions	Sep. 30, 2020 USD ($)
Commercial Portfolio Segment
Schedule of Investments [Line Items]
Gross Carrying Value	$ 546
Allowance for expected credit loss	(2)
Total commercial mortgage loans	$ 544
% of Total	100.00%
East North Central
Schedule of Investments [Line Items]
Gross Carrying Value	$ 63
% of Total	12.00%
East South Central
Schedule of Investments [Line Items]
Gross Carrying Value	$ 51
% of Total	9.00%
Middle Atlantic
Schedule of Investments [Line Items]
Gross Carrying Value	$ 77
% of Total	14.00%
Mountain
Schedule of Investments [Line Items]
Gross Carrying Value	$ 48
% of Total	9.00%
New England
Schedule of Investments [Line Items]
Gross Carrying Value	$ 43
% of Total	8.00%
Pacific
Schedule of Investments [Line Items]
Gross Carrying Value	$ 126
% of Total	23.00%
South Atlantic
Schedule of Investments [Line Items]
Gross Carrying Value	$ 67
% of Total	12.00%
West North Central
Schedule of Investments [Line Items]
Gross Carrying Value	$ 13
% of Total	2.00%
West South Central
Schedule of Investments [Line Items]
Gross Carrying Value	$ 58
% of Total	11.00%
Hotel
Schedule of Investments [Line Items]
Gross Carrying Value	$ 19
% of Total	3.00%
Industrial - General
Schedule of Investments [Line Items]
Gross Carrying Value	$ 11
% of Total	2.00%
Industrial - Warehouse
Schedule of Investments [Line Items]
Gross Carrying Value	$ 12
% of Total	2.00%
Multifamily
Schedule of Investments [Line Items]
Gross Carrying Value	$ 113
% of Total	21.00%
Office
Schedule of Investments [Line Items]
Gross Carrying Value	$ 107
% of Total	20.00%
Retail
Schedule of Investments [Line Items]
Gross Carrying Value	$ 141
% of Total	26.00%
Other
Schedule of Investments [Line Items]
Gross Carrying Value	$ 143
% of Total	26.00%

Percentage of the total commercial loan portfolio.

No definition available.

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- Definition

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=121614798&loc=d3e15032-111544

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953423-111524

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SAB Topic 6.L.1)
-URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74567-122707

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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121593590&loc=d3e4428-111522

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7)
-URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878

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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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