Fair Value Measurement - Nonrecurring Fair Value Measurements Included in Earnings (Detail) - Nonrecurring - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Loans held for investment	$ 187	$ (189)
Loans held for sale	0	(1)
Other assets	(42)	(60)
Total	$ 145	$ (250)

Gain (Loss) On Fair Value Assets measured on nonrecurring basis

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- Definition

Gain (Loss) On Fair Value Loans Held For Investment measured on nonrecurring basis

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- Definition

Gain (Loss) On Fair Value Loans Held For Sale measured on nonrecurring basis

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- Definition

Gain (Loss) On Fair Value Other Assets measured on nonrecurring basis

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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.

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