Loans and Loans Held for Sale - Additional Information (Detail) (USD $)	Dec. 31, 2014
Loans Receivables [Abstract]
Minimum future lease payment to be received, 2015	$ 1,000,000,000
Minimum future lease payment to be received, 2016	767,000,000
Minimum future lease payment to be received, 2017	474,000,000
Minimum future lease payment to be received, 2018	276,000,000
Minimum future lease payment to be received, 2019	156,000,000
Minimum future lease payment to be received, subsequent years	169,000,000
Allowance related to lease financing receivables	$ 56,000,000

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Amount of minimum lease payments to be received by the lessor for capital leases in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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=25496975&loc=d3e45377-112738

+ Details

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

Amount of minimum lease payments to be received by the lessor for capital leases in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

+ Details

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- Definition

The estimate of contractual payments on direct financing leases that are probable of not being collected as of the balance sheet date.

+ 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 (a)(1)(ii)

-URI http://asc.fasb.org/extlink&oid=25496975&loc=d3e45377-112738

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