Borrowings - Stated Maturities and Maturities to Call Dates (Parenthetical) (Detail) (USD $) In Billions, unless otherwise specified	Dec. 31, 2013
Debt Disclosure [Abstract]
On-balance sheet securitization trust debt included in projected principal paydowns in 2014	$ 14.4
Aggregate principal amount of debt maturing in 2014	14.5
Aggregate principal amount of debt maturing in 2015	14.4
Aggregate principal amount of debt maturing in 2016	12.5
Aggregate principal amount of debt maturing in 2017	12.6
Aggregate principal amount of debt maturing in 2018	11.9
Aggregate principal amount of debt maturing in 2019 and after	$ 69.6

On-balance sheet securitization trust debt included in projected principal paydowns in following year.

No definition available.

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing after the fifth fiscal year following the latest fiscal year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 470

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6802200&loc=d3e1835-112601

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the next fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fifth fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the fourth fiscal year following the latest fiscal year.

+ References

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Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the third fiscal year following the latest fiscal year.

+ References

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- Definition

Amount of long-term debt, sinking fund requirements, and other securities redeemable at fixed or determinable prices and dates maturing in the second fiscal year following the latest fiscal year.

+ References

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