Federal Home Loan Bank Stock (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Federal Home Loan Bank Stock [Abstract]
Federal Home Loan Bank stock	$ 377	$ 303
Federal Home Loan Bank stock, minimum investment requirement, percentage of unpaid principal of mortgage loans, home purchase contracts and similar obligations (in percentage)	1.00%
Federal Home Loan Bank minimum percentage of advances required held (in percentage)	4.50%
Payments to acquire FHLB stock	$ 74	0
Dividend income	$ 12	$ 16	$ 15

The minimum investment percentage of Federal Home Loan Advances as a member of the FHLB.

No definition available.

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

No definition available.

+ Details

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- Definition

Minimum investment percentage of unpaid principal of mortgage loans, home purchase contracts and similar obligations for investment in Federal Home Loan Bank (FHLB) stock as a member of the FHLB.

+ References

No definition available.

+ Details

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- Definition

Federal Home Loan Bank (FHLB) stock represents an equity interest in a FHLB. It does not have a readily determinable fair value because its ownership is restricted and it lacks a market (liquidity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 325
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=75031641&loc=d3e63345-112809

+ Details

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- Definition

Amount of dividend income on nonoperating securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7(a))
-URI http://asc.fasb.org/extlink&oid=120395209&loc=SL114868664-224227

+ Details

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- Definition

Amount of cash outflow to acquire Federal Home Loan Bank (FHLB) stock.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3213-108585

+ Details

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