PARENT COMPANY CONDENSED FINANCIAL STATEMENTS: (Details 2) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss) Attributable to Parent	$ 15,739	$ 14,000	$ 11,924	$ 12,181	$ 14,364	$ 12,257	$ 12,569	$ 9,682	$ 53,844	$ 48,872	$ 46,583
Adjustments to reconcile net income to net cash provided by operating activities:
Contribution of shares to ESOP									1,471	1,251	1,087
NET CASH FROM OPERATING ACTIVITIES									77,425	49,901	57,448
CASH FLOWS FROM INVESTING ACTIVITIES:
NET CASH FROM INVESTING ACTIVITIES									(16,248)	(32,866)	(34,324)
CASH FLOWS FROM FINANCING ACTIVITIES:
Purchases of treasury stock									(9,220)	(315)	(391)
Dividends paid									(14,273)	(12,648)	(12,496)
NET CASH FROM FINANCING ACTIVITIES									468,867	36,003	(22,843)
Supplemental disclosures of cash flow information:
Income Taxes									7,549	9,595	7,185
Parent
CASH FLOWS FROM OPERATING ACTIVITIES:
Net Income (Loss) Attributable to Parent									53,844	48,872	46,583
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization									328	193	193
Equity in undistributed earnings									(24,724)	(29,568)	(34,092)
Contribution of shares to ESOP									1,471	1,251	1,087
Restricted stock compensation									820	801	745
Increase (decrease) in other liabilities									6,127	(2,150)	(585)
(Increase) decrease in other assets									(5,977)	1,187	(900)
NET CASH FROM OPERATING ACTIVITIES									31,889	20,586	13,031
CASH FLOWS FROM INVESTING ACTIVITIES:
Payments to Acquire Interest in Subsidiaries and Affiliates									0	6,571	0
NET CASH FROM INVESTING ACTIVITIES									0	(6,571)	0
CASH FLOWS FROM FINANCING ACTIVITIES:
Purchases of treasury stock									(9,220)	(315)	(391)
Dividends paid									(14,273)	(12,648)	(12,496)
NET CASH FROM FINANCING ACTIVITIES									(33,803)	(12,963)	(12,887)
NET CHANGE IN CASH AND CASH EQUIVALENTS									(1,914)	1,052	144
CASH AND DUE FROM BANKS, BEGINNING OF YEAR				$ 4,394				$ 3,342	4,394	3,342	3,198
CASH AND DUE FROM BANKS, END OF YEAR	$ 2,480				$ 4,394				2,480	4,394	3,342
Supplemental disclosures of cash flow information:
Interest									375	0	0
Income Taxes									$ 7,538	$ 9,595	$ 7,185