Acquisition, Divestiture and Discontinued Operations (Details 1) (Segment, Discontinued Operations [Member], Education Lending [Member])	12 Months Ended
Dec. 31, 2011 Y
Maximum [Member]
Assumptions used to measure fair value of assets and liabilities of the trusts
Weighted-average life (years)	5.9
PREPAYMENT SPEED ASSUMPTIONS (ANNUAL RATE)	26.00%
EXPECTED CREDIT LOSSES	80.00%
LOAN DISCOUNT RATES (ANNUAL RATE)	10.59%
SECURITY DISCOUNT RATES (ANNUAL RATE)	9.60%
EXPECTED DEFAULTS (STATIC RATE)	40.00%
Minimum [Member]
Assumptions used to measure fair value of assets and liabilities of the trusts
Weighted-average life (years)	1.4
PREPAYMENT SPEED ASSUMPTIONS (ANNUAL RATE)	4.00%
EXPECTED CREDIT LOSSES	2.00%
LOAN DISCOUNT RATES (ANNUAL RATE)	2.57%
SECURITY DISCOUNT RATES (ANNUAL RATE)	2.28%
EXPECTED DEFAULTS (STATIC RATE)	3.75%

Annual discount rates on Security.

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- Definition

Assumption For Fair Value Of Interests Continued To Be Held By Transferor Servicing Assets Or Liabilities Expected Defaults.

+ References

No definition available.

+ Details

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- Definition

The discount rate which is used to value residual cash flows generated by financial assets of the securitization or asset-backed financing arrangement. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

+ References

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

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS140-4 and FIN46(R)-8

-Paragraph B11

-Subparagraph b(3)

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 140

-Paragraph 17

-Subparagraph i(2)

+ Details

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- Definition

The rate at which principal will not be repaid on securitized financial assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

+ References

+ Details

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- Definition

Estimated speed of prepayments of principal on financial assets. This is used as a key assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

+ References

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- Definition

The weighted average life of securitized assets. This is used as a key input and assumption in measuring the fair value of assets or liabilities that relate to a transferor's continuing involvement (including interests that continue to be held by the transferor and servicing assets or servicing liabilities), if any, as of the date of the latest statement of financial position presented.

+ References

+ Details

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