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Variable Interest Entities - Summary of the Impact of Qualifying LIHTC Investments (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
LIHTC credits and benefits, net of amortization	$ (9)	$ (4)	$ (7)
Low income housing tax credits
Variable Interest Entity [Line Items]
Amortization of qualifying LIHTC investments	23	15	11
LIHTC credits and benefits, net of amortization	(22)	(14)	(10)
Other tax benefits related to qualifying LIHTC investments
Variable Interest Entity [Line Items]
LIHTC credits and benefits, net of amortization	$ (10)	$ (6)	$ (7)

X

- Definition

Amount of affordable housing tax credits and other tax benefits recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

+ Details

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X

- Definition

Amount of amortization expense of investment in qualified affordable housing projects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=116633289&loc=SL49122993-202985

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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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