Investment in Receivables - Scheduled Minimum Lease Payments on Finance Leases and Scheduled Principal Payments on Notes and Other Receivables (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012
Future Years Payment [Line Items]
2013	$ 234
2014	175
2015	175
2016	175
2017	163
Thereafter	768
2013	382
2014	98
2015	57
2016	41
2017	42
Thereafter	$ 157

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Notes receivables Future Principal Payments, Receivable Current

+ References

No definition available.

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- Definition

Notes receivables Future Principal Payments, Receivable Due Thereafter

+ References

No definition available.

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- Definition

Notes receivables Future Principal Payments, Receivable in Five Years

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No definition available.

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- Definition

Notes receivables Future Principal Payments, Receivable in Four Years

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No definition available.

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- Definition

Notes receivables Future Principal Payments, Receivable in Three Years

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No definition available.

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- Definition

Notes receivables Future Principal Payments, Receivable in Two Years

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- Definition

Amount of minimum lease payments to be received by the lessor in the next fiscal year following the latest fiscal year for capital leases.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 50

-Paragraph 4

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6952072&loc=d3e45377-112738

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 23

-Subparagraph a(ii)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Amount of minimum lease payments to be received by the lessor after the fifth fiscal year following the latest fiscal year for capital leases.

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- Definition

Amount of minimum lease payments to be received by the lessor in the fifth fiscal year following the latest fiscal year for capital leases.

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Amount of minimum lease payments to be received by the lessor in the fourth fiscal year following the latest fiscal year for capital leases.

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- Definition

Amount of minimum lease payments to be received by the lessor in the third fiscal year following the latest fiscal year for capital leases.

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- Definition

Amount of minimum lease payments to be received by the lessor in the second fiscal year following the latest fiscal year for capital leases.

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