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Fair Value Measurement - Nonrecurring Fair Value Measurements Included in Earnings (Detail) - Nonrecurring - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	$ (207)	$ (75)
Loans held for sale	0	(1)
Other assets	(44)	(49)
Total	$ (251)	$ (125)

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- Definition

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- Definition

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