Supplemental Cash Flow (Noncash Investing and Financing Activities) (Detail) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Interest paid
Interest	$ 578	$ 475	$ 429
Cash Payments:
Income taxes	800	400	550
Noncash Investing and Financing Activities:
Portfolio loans to loans held for sale	238	487	855
Loans held for sale to portfolio loans	28	288	31
Portfolio loans to OREO	49	105	145
Loans held for sale to OREO	0	0	2
Capital lease	$ 0	$ 4	$ 15

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

No definition available.

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- Definition

Value of real estate transferred in noncash transactions from held for sale to other real estate owned during the reporting period.

+ References

No definition available.

+ Details

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- Definition

The increase during the period in capital lease obligations due to entering into new capital leases.

+ References

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
-Paragraph 25
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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- References

No definition available.

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- Definition

The amount of cash paid for interest during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4297-108586

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-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3536-108585

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- References

No definition available.

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4313-108586

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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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6367179&loc=d3e4304-108586

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