LOANS (Schedule of Loan Balances by Portfolio Class) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Total loans	$ 4,389,641	$ 3,924,312
Net deferred costs	4,496	3,619
Total loans including net deferred costs	$ 4,394,137	$ 3,927,931
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	$ 578,306	$ 600,891
Residential Portfolio Segment [Member] \| Primary Residential Mortgages [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	13.17%	15.31%
Residential Portfolio Segment [Member] \| Home Equity Lines of Credit [Member]
Total loans	$ 57,248	$ 62,191
Total loans including net deferred costs	$ 57,248	$ 62,191
Residential Portfolio Segment [Member] \| Home Equity Lines of Credit [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.30%	1.58%
Residential Portfolio Segment [Member] \| Multifamily Property [Member]
Total loans	$ 1,210,003	$ 1,135,805
Total loans including net deferred costs	$ 1,210,003	$ 1,135,805
Residential Portfolio Segment [Member] \| Multifamily Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	27.56%	28.94%
Residential Portfolio Segment [Member] \| Junior Lien [Member]
Total loans	$ 7,011	$ 7,418
Residential Portfolio Segment [Member] \| Junior Lien [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.16%	0.19%
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Property [Member]
Total loans	$ 249,419	$ 261,193
Commercial Real Estate Portfolio Segment [Member] \| Owner Occupied Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	5.68%	6.65%
Commercial Real Estate Portfolio Segment [Member] \| Investment Property [Member]
Total loans	$ 1,095,182	$ 1,001,918
Commercial Real Estate Portfolio Segment [Member] \| Investment Property [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	24.95%	25.53%
Commercial Portfolio Segment [Member] \| Construction [Member]
Total loans	$ 5,520	$ 86
Total loans including net deferred costs	$ 5,306
Commercial Portfolio Segment [Member] \| Construction [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.07%	0.01%
Consumer and Other Loans [Member]
Total loans	$ 58,213	$ 65,180
Consumer and Other Loans [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	1.33%	1.66%
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member]
Total loans	$ 867,295	$ 616,838
Commercial and Industrial Sector [Member] \| Commercial Portfolio Segment [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	19.76%	15.72%
Lease Financing [Member]
Total loans	$ 258,401	$ 172,643
Lease Financing [Member] \| Commercial Portfolio Segment [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	5.89%	4.40%
Agricultural Sector [Member]
Total loans	$ 3,043	$ 149
Agricultural Sector [Member] \| Customer Concentration Risk [Member] \| Loans and Finance Receivables, Gross [Member]
Total loans (in percent)	0.13%	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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