Discontinued Operations - Cross-Border Energy Lease Investments (Detail) (USD $) In Millions, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Discontinued Operations And Disposal Groups [Abstract]
Scheduled lease payments to PHI, net of non-recourse debt		$ 1,852
Less: Unearned and deferred income		(615)
Assets held for disposition		1,237
Liabilities associated with assets held for disposition	$ 1	$ 1

Leveraged leases net investment in leveraged leases minimum payments to be received.

No definition available.

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- Definition

Liabilities Of Assets Held For Disposition

+ References

No definition available.

+ Details

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- Definition

Long-lived assets that are held for sale apart from normal operations and anticipated to be sold in less than one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

+ Details

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- Definition

The estimated portion of pretax income and investment tax credit remaining to be allocated to income over the lease term.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 30

-Paragraph 14

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=7662307&loc=d3e42840-112730

+ Details

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