LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Dec. 31, 2015	Jun. 30, 2016
Total loans	$ 2,911,552	$ 3,147,304
Net deferred fees	1,690	1,595
Total loans including net deferred costs	2,913,242	3,148,899
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	11,503	10,476
Consumer and Other [Member]
Total loans	47,635	72,844
Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans	483,085	510,062
Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans	52,804	63,188
Total loans including net deferred costs	52,649	63,188
Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans	1,416,775	1,501,915
Total loans including net deferred costs	1,416,775	1,501,915
Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	176,276	166,124
Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	568,849	642,530
Construction Loans [Member]
Total loans including net deferred costs	1,401
Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans	151	99
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans	154,295	179,892
Agricultural Sector [Member]
Total loans	$ 179	$ 174
Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	100.00%	100.00%
Loans and Finance Receivables, Gross [Member] \| Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans (in percent)	0.39%	0.33%
Loans and Finance Receivables, Gross [Member] \| Consumer and Other [Member]
Total loans (in percent)	1.64%	2.31%
Loans and Finance Receivables, Gross [Member] \| Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	16.59%	16.21%
Loans and Finance Receivables, Gross [Member] \| Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	1.81%	2.01%
Loans and Finance Receivables, Gross [Member] \| Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	48.66%	47.72%
Loans and Finance Receivables, Gross [Member] \| Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	6.05%	5.28%
Loans and Finance Receivables, Gross [Member] \| Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	19.54%	20.41%
Loans and Finance Receivables, Gross [Member] \| Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	0.01%
Loans and Finance Receivables, Gross [Member] \| Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	5.30%	5.72%
Loans and Finance Receivables, Gross [Member] \| Agricultural Sector [Member]
Total loans (in percent)	0.01%	0.01%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
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-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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