Supplemental Cash Flow (Noncash Investing and Financing Activities) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Interest paid
Interest	$ 1,016	$ 699	$ 578
Cash Payments:
Income taxes	359	1,035	800
Noncash Investing and Financing Activities:
Portfolio loans to loans held for sale	275	255	238
Loans held for sale to portfolio loans	95	29	28
Portfolio loans to OREO	$ 39	$ 34	$ 49

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

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to 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; classified as operating and investing activities.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4297-108586

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- References

No definition available.

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- Definition

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

+ References

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- Definition

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

+ References

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