LOANS: (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 2,606,113	$ 2,652,530
Deferred costs, net	4,181	3,860
Allowance for credit losses	(47,052)	(19,943)	$ (20,436)	$ (19,909)
TOTAL	2,563,242	2,636,447
Commercial
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	1,521,711	1,584,447
Residential
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	604,652	682,077
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans	$ 479,750	$ 386,006