LOANS RECEIVABLE AND CREDIT QUALITY, Troubled Debt Restructurings (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015 Loan	Dec. 31, 2014 Loan	Mar. 31, 2014
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	10	11
Financing Receivable, Modifications, Recorded Investment	$ 14,287	$ 19,817
Financing Receivables Modification Accrual Status Number Of Contracts	7	9
Financing Receivable Modification Recorded Investment In Accrual Status	9,199	15,100
Financing Receivables Modification Non Accrual Status Number Of Contracts	3	2
Financing Receivable Modification Recorded Investment In Non Accrual Status	5,088	4,717
Allocated Reserves Recognized For Trouble Debt Restructuring Receivables That Defaulted	0	19
One To Four Family Residential And Cooperative Unit Allowance [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	2	2
Financing Receivable, Modifications, Recorded Investment	603	605
Multifamily Residential and Residential Mixed Use [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	4	4
Financing Receivable, Modifications, Recorded Investment	1,092	1,105
Mixed Use Commercial Real Estate [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	1	1
Financing Receivable, Modifications, Recorded Investment	4,400	4,400
Commercial Real Estate [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	3	4
Financing Receivable, Modifications, Recorded Investment	8,192	13,707
Total Real Estate Loans [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Premium paid on loans purchased during the period	$ 0		$ 13,163

Amounts allocated within the allowance for loan losses related to troubled debt restructured loans at period end.

No definition available.

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings and are in accrual status.

+ References

No definition available.

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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings and are in non-accrual status

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings and are in accrual status.

+ References

No definition available.

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Number of financing receivables that have been modified by troubled debt restructurings and are in non-accrual status.

+ References

No definition available.

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- Definition

The aggregate premium paid on loans purchased during the period to be recognized as an adjustment to the yield on the loans over their respective remaining lives.

+ References

No definition available.

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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