Supplemental Cash Flow (Noncash Investing and Financing Activities) (Detail) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Cash Payments:
Interest	$ 367	$ 379
Income taxes	14	14
Transfers:
Portfolio loans and leases to loans and leases held for sale	23	38
Loans and leases held for sale to portfolio loans and leases	7	15
Portfolio loans and leases to OREO	5	8
Supplemental Disclosures:
Additions to right-of-use assets under operating leases	17	4
Additions to right-of-use assets under finance leases	13	1
Right-of-use assets recognized at adoption of ASU 2016-02	$ 0	$ 509

Right of use assets obtain in exchange for liabilities.

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The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Value of loans held-for-sale transferred to loans held in the entity's portfolio in noncash transactions.

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Value transferred from mortgage loans to real estate owned (REO) in noncash transactions.

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