LOANS RECEIVABLE AND ALLOWANCE FOR CREDIT LOSSES (Details 2) - Loans Receivable $ in Millions	9 Months Ended
Sep. 30, 2015 USD ($) property_unit grade	Dec. 31, 2014 USD ($)
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Loans receivable pledged to secure borrowings and to provide additional borrowing capacity from the FHLB and the Federal Reserve Bank \| $	$ 15,730	$ 14,660
Number of grades in the risk rating system utilized by the company to rate credit risk of loans receivable \| grade	7
Residential \| Single-family \| Minimum
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Number of units of residential property securing fixed and adjustable rate first mortgage loans	1
Adjustable rate mortgage, term of initial fixed interest rates	1 year
Residential \| Single-family \| Maximum
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Number of units of residential property securing fixed and adjustable rate first mortgage loans	4
Adjustable rate mortgage, term of initial fixed interest rates	3 years
Residential \| Multifamily \| Minimum
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Adjustable rate mortgage, term of initial fixed interest rates	6 months
Residential \| Multifamily \| Maximum
LOANS RECEIVABLE AND ALLOWANCE FOR LOAN LOSSES
Adjustable rate mortgage, term of initial fixed interest rates	3 years

The term for an initial interest rate period of an adjustable rate mortgage.

No definition available.

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- Definition

The number of grades in the risk rating system utilized by the company to rate credit risk of loans receivable. Loans are risk rated based on analysis of the current state of the borrower's credit quality. Higher grades represent a higher level of credit risk.

+ References

No definition available.

+ Details

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- Definition

The number of units in residential property that secures both fixed and adjustable rate first mortgage loans.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 860

-SubTopic 30

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6467456&loc=d3e113888-111728

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=49124121&loc=d3e5086-111524

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