LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Dec. 31, 2015
Total loans	$ 3,025,837	$ 2,911,552
Net deferred fees	1,864	1,690
Total loans including net deferred costs	$ 3,027,701	$ 2,913,242
Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	100.00%	100.00%
Agricultural Sector [Member]
Total loans	$ 177	$ 179
Agricultural Sector [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.01%	0.01%
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	$ 10,686	$ 11,503
Residential Portfolio Segment [Member] \| Junior Lien [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.35%	0.39%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Total loans	$ 173,299	$ 154,295
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	5.73%	5.30%
Consumer and Other [Member]
Total loans	$ 47,894	$ 47,635
Consumer and Other [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.58%	1.64%
Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans	$ 499,734	$ 483,085
Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	16.52%	16.59%
Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans	$ 53,481	$ 52,804
Total loans including net deferred costs	$ 53,328	$ 52,649
Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.77%	1.81%
Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans	$ 1,489,708	$ 1,416,775
Total loans including net deferred costs	$ 1,489,708	$ 1,416,775
Multifamily Property [Member] \| Residential Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	49.22%	48.66%
Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	$ 163,495	$ 176,276
Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	5.40%	6.05%
Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	$ 587,213	$ 568,849
Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	19.41%	19.54%
Construction Loans [Member]
Total loans including net deferred costs	$ 1,392	$ 1,401
Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans	$ 150	$ 151
Construction Loans [Member] \| Commercial Portfolio Segment [Member] \| Loans and Finance Receivables, Gross [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
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-Section 50
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