LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Dec. 31, 2015	Sep. 30, 2016
Total loans	$ 2,911,552	$ 3,230,890
Net deferred fees	1,690	1,997
Total loans including net deferred costs	2,913,242	3,232,887
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	11,503	10,046
Consumer and Other [Member]
Total loans	47,635	74,141
Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans	483,085	527,012
Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans	52,804	62,870
Total loans including net deferred costs	52,649	69,222
Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans	1,416,775	1,507,834
Total loans including net deferred costs	1,416,775	1,507,834
Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	176,276	179,285
Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	568,849	676,468
Construction Loans [Member]
Total loans including net deferred costs	1,401	430
Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans	151	523
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans	154,295	192,539
Agricultural Sector [Member]
Total loans	$ 179	$ 172
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%	0.31%
Loans and Finance Receivables, Gross [Member] \| Consumer and Other [Member]
Total loans (in percent)	1.64%	2.29%
Loans and Finance Receivables, Gross [Member] \| Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	16.59%	16.31%
Loans and Finance Receivables, Gross [Member] \| Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	1.81%	1.94%
Loans and Finance Receivables, Gross [Member] \| Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	48.66%	46.67%
Loans and Finance Receivables, Gross [Member] \| Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	6.05%	5.55%
Loans and Finance Receivables, Gross [Member] \| Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	19.54%	20.94%
Loans and Finance Receivables, Gross [Member] \| Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	0.01%	0.02%
Loans and Finance Receivables, Gross [Member] \| Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	5.30%	5.96%
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
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=64851502&loc=d3e6351-108592

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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