LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	9 Months Ended	12 Months Ended
Sep. 30, 2018	Dec. 31, 2017
Total loans	$ 3,795,230	$ 3,702,532
Net deferred costs	3,360	1,908
Total loans including net deferred costs	$ 3,798,590	$ 3,704,440
Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	100.00%	100.00%
Residential Portfolio Segment [Member] \| Primary Residential Mortgages [Member]
Total loans	$ 592,283	$ 605,569
Residential Portfolio Segment [Member] \| Primary Residential Mortgages [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	15.61%	16.35%
Residential Portfolio Segment [Member] \| Home Equity Lines of Credit [Member]
Total loans	$ 59,929	$ 67,497
Total loans including net deferred costs	$ 59,930	$ 67,497
Residential Portfolio Segment [Member] \| Home Equity Lines of Credit [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.58%	1.82%
Residential Portfolio Segment [Member] \| Multifamily Property [Member]
Total loans	$ 1,285,816	$ 1,388,958
Total loans including net deferred costs	$ 1,285,816	$ 1,388,958
Residential Portfolio Segment [Member] \| Multifamily Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	33.88%	37.51%
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	$ 7,531	$ 7,073
Residential Portfolio Segment [Member] \| Junior Lien [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.20%	0.19%
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Property [Member]
Total loans	$ 249,170	$ 253,492
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	6.57%	6.85%
Commercial Real Estate Portfolio Segment [Member] \| Investment Property [Member]
Total loans	$ 901,820	$ 874,098
Commercial Real Estate Portfolio Segment [Member] \| Investment Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	23.76%	23.61%
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Total loans	$ 88	$ 92
Commercial Portfolio Segment [Member] \| Construction Loans [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)		0.01%
Consumer and Other Loans [Member]
Total loans	$ 67,489	$ 99,247
Consumer and Other Loans [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.78%	2.68%
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans	$ 479,763	$ 316,294
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	12.64%	8.54%
Lease Financing [Member]
Total loans	$ 151,189	$ 90,052
Lease Financing [Member] \| Commercial Portfolio Segment [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	3.98%	2.43%
Agricultural Sector [Member]
Total loans	$ 152	$ 160
Agricultural Sector [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)		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.

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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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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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