Receivables - Narrative (Detail) - Loans and finance receivables [Member] - Finance and Financial Products [Member] - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2015	Jun. 30, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Provisions for loan losses	$ 77	$ 94
Loan charge-offs, net of recoveries	93	$ 102
Allowances in uncollectible loans and related installment loan receivables reclassified to other assets	$ 93
Percent of loan balances evaluated collectively for impairment	98.00%
Percent of loan balances that are performing	99.00%
Percent of loan balances that are current as to payment status	96.00%

Percent of loan balances evaluated collectively for impairment.

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- Definition

Percent of loan balances that are performing.

+ References

No definition available.

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- Definition

Percent of loan balances that are current as to payment status.

+ References

No definition available.

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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.

+ References

No definition available.

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- Definition

Amount of other addition (reduction) in allowance reserve for credit loss.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 15

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(d))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

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

+ References

No definition available.

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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 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.11)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (c)(2)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

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