Asset Quality - Allowance for Loan and Lease Losses (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Receivables [Abstract]
Balance at beginning of period - continuing operations	$ 848	$ 888	$ 1,004
Charge-offs	(211)	(308)	(508)
Recoveries	98	140	163
Net loans and leases charged off	(113)	(168)	(345)
Provision for loan and lease losses from continuing operations	59us-gaap_ProvisionForLoanAndLeaseLosses	130us-gaap_ProvisionForLoanAndLeaseLosses	229us-gaap_ProvisionForLoanAndLeaseLosses
Foreign currency translation adjustment		(2)
Balance at end of period - continuing operations	$ 794	$ 848	$ 888

Financing receivable allowance for credit losses foreign currency translation adjustment.

No definition available.

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- Definition

Amount, after recoveries, of loans and leases that have been written-off.

+ References

No definition available.

+ Details

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- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(1)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(4)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 11

-Article 9

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

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