INCOME TAXES: (Details 1) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Federal income taxes computed at the statutory rate	$ 12,810	$ 12,122	$ 17,414
Add (deduct) tax effect of:
Tax exempt income	(2,551)	(2,495)	(4,102)
THFF FSI non-deductable goodwill	0	0	0
ESOP dividend deduction	(115)	(103)	(102)
State tax, net of federal benefit	2,034	1,846	1,483
Affordable housing credits	(148)	(148)	(148)
Federal tax reform	0	0
Other, net	97	(77)	(205)
TOTAL	$ 12,127	$ 11,145	$ 20,622

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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