PARENT COMPANY CONDENSED FINANCIAL STATEMENTS: (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
ASSETS
Cash deposits in affiliated banks	$ 127,426	$ 74,388
Land and headquarters building, net	62,576	46,554
Other	41,556	22,607
TOTAL ASSETS	4,023,250	3,008,718
LIABILITIES AND SHAREHOLDERS' EQUITY
Other liabilities	79,193	59,634
TOTAL LIABILITIES	3,465,642	2,566,017
Shareholders' Equity	557,608	442,701	$ 413,569	$ 414,395
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	4,023,250	3,008,718
Parent
ASSETS
Cash deposits in affiliated banks	4,394	3,342
Investments in subsidiaries	566,384	442,547
Land and headquarters building, net	4,807	5,000
Other	23	900
TOTAL ASSETS	575,608	451,789
LIABILITIES AND SHAREHOLDERS' EQUITY
Dividends payable	7,142	6,258
Other liabilities	681	2,830
TOTAL LIABILITIES	18,000	9,088
Shareholders' Equity	557,608	442,701
TOTAL LIABILITIES AND SHAREHOLDERS’ EQUITY	$ 575,608	$ 451,789