SECURITIZATIONS AND VARIABLE INTEREST ENTITIES (Details 7) (USD $)	3 Months Ended	6 Months Ended
Jun. 30, 2011 Mortgage servicing rights	Jun. 30, 2010 Mortgage servicing rights	Jun. 30, 2011 Mortgage servicing rights	Jun. 30, 2010 Mortgage servicing rights
Mortgage servicing rights:
Classification of Securitizations
Principal amount of loans and other financial instruments	$ 433,000,000,000	$ 509,000,000,000	$ 433,000,000,000	$ 509,000,000,000
Fair value of capitalized mortgage servicing rights	4,300,000,000	4,900,000,000	4,300,000,000	4,900,000,000
Re-securitizations
Balance at beginning of period	4,690,000,000	6,439,000,000	4,554,000,000	6,530,000,000
Originations	105,000,000	117,000,000	299,000,000	269,000,000
Changes in fair value of MSRs due to changes in inputs and assumptions	(277,000,000)	(1,384,000,000)	(105,000,000)	(1,294,000,000)
Other changes	(260,000,000)	(278,000,000)	(490,000,000)	(611,000,000)
Balance at end of period	4,258,000,000	4,894,000,000	4,258,000,000	4,894,000,000
Servicing fees	301,000,000	344,000,000	605,000,000	713,000,000
Late fees	18,000,000	21,000,000	39,000,000	44,000,000
Ancillary fees	25,000,000	53,000,000	53,000,000	92,000,000
Total MSR fees	344,000,000	418,000,000	697,000,000	849,000,000
Non-agency-sponsored mortgages
Re-securitizations
Securities transferred to re-securitization entities			136,000,000
Original par value of re-securitizations deals in which the entity holds a retained interest	361,000,000		361,000,000
Market value of retained interest related to re-securitization transaction in 2011	30,000,000		30,000,000
Senior beneficial interests	83,000,000		83,000,000
Subordinated beneficial interests	278,000,000		278,000,000
Assumption for Fair Value on Securitization Date of Interests Continued to be Held by Transferor Servicing Assets or Liabilities Low End Weighted Average Life			0.8
U.S. government-sponsored agency guaranteed
Re-securitizations
Securities transferred to re-securitization entities			21,300,000,000
Original par value of re-securitizations deals in which the entity holds a retained interest	8,000,000,000		8,000,000,000
Market value of interest in U.S. government sponsored agency guaranteed re-securitization entities	2,600,000,000		2,600,000,000
Market value of retained interest related to re-securitization transaction in 2011	2,200,000,000		2,200,000,000
Original fair value of re-securitizations deals in which the entity holds a retained interest	$ 49,400,000,000		$ 49,400,000,000

This element represents the low end of the range of 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, at the time of securitization or asset-backed financing.

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Balance Type:	debit
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- Definition

This element represents the amount of market value of interest owned by the entity in private-label re-securitization entities.

+ Details

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- Definition

This element represents the amount of market value of interest owned by the entity in private-label re-securitization entities, for current period.

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- Definition

Represents the amount of original fair value of re-securitizations deals in which the entity holds a retained interest.

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- Definition

Represents the amount of original par value of re-securitizations deals in which the entity holds a retained interest.

+ Details

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- Definition

Represents the amount of securities transferred to re-securitization entities.

+ Details

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- Definition

Obligation reflecting another party's senior right to economic interests in another entity or trust under a contractual right.

+ Details

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Balance Type:	credit
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- Definition

Obligation reflecting another party's subordinate right to economic interests in another entity or trust under a contractual right.

+ Details

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- Definition

All amounts that are due to the servicer of a financial asset, excluding contractually specified servicing fees and late fees.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The amount of servicing fees from the securitization or asset-backed financing arrangement SPE.

+ 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 a(3)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph h(4)

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ 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 B8
-Subparagraph c

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
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-Paragraph 17
-Subparagraph e(3)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 20

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Balance Type:	credit
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- Definition

All amounts that are due to the servicer of a financial asset as a result of the debt holder not meeting the monthly payment terms.

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This includes both the securitized and unsecuritized portion of the total principal amount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph i(4)

Reference 2: 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(1)(b), b(6)

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- Definition

The value of new servicing assets acquired or created during the current period through purchases, assumptions of servicing obligations, and servicing obligations that result from transfers of financial assets.

+ 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 B9
-Subparagraph a(2)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph f(1)(b)

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- Definition

Fair value as of the balance sheet date of an asset representing net future revenues from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements. The fair value of an asset is the amount at which that asset could be bought or sold (or settled) in a current transaction between willing parties, other than in a forced or liquidation sale. Rights may be obtained via (1) acquisition or assumption of a servicing obligation that does not relate to financial assets of the servicer or its consolidated affiliates; or (2) by originating loans and then (a) transferring the loans to a qualifying special purpose entity in a transaction that meets the necessary transfer and classification requirements, or (b) transferring the loans in a transaction that meets the requirements for sale accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 13A, 13B

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name FASB Staff Position (FSP)
-Number FAS140-4 and FIN46(R)-8
-Paragraph B9
-Subparagraph a(1)

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

The net increase (decrease) in fair value as a result of changes in the inputs, assumptions, or model used to calculate the fair value of servicing assets.

+ 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 B9
-Subparagraph a(4)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph f(1)(d)

+ Details

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- Definition

Other net increase (decrease) in the balance in servicing assets subsequently measured at fair value. This element is for changes other than additions, disposals, changes in fair value resulting from changes in valuation inputs or changes in assumptions, or other changes in fair value.

+ 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 B9
-Subparagraph a(5)

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 140
-Paragraph 17
-Subparagraph f(1)(e)

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