LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Dec. 31, 2016
Total loans	$ 3,438,236	$ 3,310,104
Net deferred fees	1,414	2,040
Total loans including net deferred costs	3,439,650	3,312,144
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	8,487	9,206
Consumer and Other [Member]
Total loans	73,880	73,621
Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans	602,436	557,970
Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans	68,055	65,683
Total loans including net deferred costs	68,055	65,682
Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans	1,468,890	1,459,594
Total loans including net deferred costs	1,468,890	1,459,594
Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	211,573	176,123
Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans	790,190	752,258
Construction Loans [Member]
Total loans including net deferred costs		1,405
Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans	96	1,497
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans	214,463	213,983
Agricultural Sector [Member]
Total loans	$ 166	$ 169
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)	0.24%	0.28%
Loans and Finance Receivables, Gross [Member] \| Consumer and Other [Member]
Total loans (in percent)	2.15%	2.22%
Loans and Finance Receivables, Gross [Member] \| Primary Residential Mortgages [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	17.52%	16.86%
Loans and Finance Receivables, Gross [Member] \| Home Equity Lines of Credit [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	1.98%	1.98%
Loans and Finance Receivables, Gross [Member] \| Multifamily Property [Member] \| Residential Portfolio Segment [Member]
Total loans (in percent)	42.72%	44.09%
Loans and Finance Receivables, Gross [Member] \| Owner Occupied Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	6.15%	5.32%
Loans and Finance Receivables, Gross [Member] \| Investment Property [Member] \| Commercial Real Estate Portfolio Segment [Member]
Total loans (in percent)	22.98%	22.73%
Loans and Finance Receivables, Gross [Member] \| Construction Loans [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	0.01%	0.04%
Loans and Finance Receivables, Gross [Member] \| Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans (in percent)	6.24%	6.47%
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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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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