LOANS: (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	$ 1,835,974	$ 1,761,323
Deferred costs, net	3,206	2,485
Allowance for loan losses	(18,773)	(19,946)	$ (18,839)	$ (20,068)
TOTAL	1,820,407	1,743,862
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	1,106,182	1,043,980
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	423,911	444,447
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total gross loans	$ 305,881	$ 272,896