VIE (Investments in Qualified Affordable Housing Tax Credits) (Detail) - Applicable income tax expense - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Schedule of Equity Method Investments
Proportional amortization	$ 5	$ 37
Tax credits and other benefits	$ (6)	$ (44)

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
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Amount of amortization expense of investment in qualified affordable housing projects.

+ References

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-Name Accounting Standards Codification
-Topic 323
-SubTopic 740
-Section 50
-Paragraph 2
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