LOANS RECEIVABLE AND CREDIT QUALITY, Troubled Debt Restructurings (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2014 Loan	Dec. 31, 2013 Loan
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	12	12
Financing Receivable, Modifications, Recorded Investment	$ 24,232	$ 24,327
Financing Receivables Modification Accrual Status Number Of Contracts	10	10
Financing Receivable Modification Recorded Investment In Accrual Status	18,525	18,620
Financing Receivables Modification Non Accrual Status Number Of Contracts	2	2
Financing Receivable Modification Recorded Investment In Non Accrual Status	5,707	5,707
Financing Receivable Modifications Number Of Contracts In Period	0
Allocated Reserves Recognized For Trouble Debt Restructuring Receivables That Defaulted	419	451
One To Four Family Residential And Cooperative Unit Allowance [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	3	3
Financing Receivable, Modifications, Recorded Investment	930	934
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	1,137	1,148
Financing Receivable Modifications Number Of Contracts In Period	0
Mixed Use Commercial Real Estate [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	0	0
Financing Receivable, Modifications, Recorded Investment	0	0
Commercial Real Estate [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Financing Receivable, Modifications, Number of Contracts	5	5
Financing Receivable, Modifications, Recorded Investment	22,165	22,245
Financing Receivable Modifications Number Of Contracts In Period	0
Total Real Estate Loans [Member]
Troubled Debt Restructuring On Receivables [Abstract]
Premium paid on loans purchased during the period	$ 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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- Definition

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.

+ Details

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- Definition

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

+ 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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- Definition

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.

+ Details

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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=28368275&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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