SECURITIES: (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	$ 1,344,790	$ 977,830
Unrealized Gains	30,126	43,354
Unrealized Losses	(10,182)	(440)
Fair Value	1,364,734	1,020,744
U.S. Government entity mortgage-backed securities
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	118,176	92,710
Unrealized Gains	2,688	5,105
Unrealized Losses	(741)	(1)
Fair Value	120,123	97,814
Mortgage-backed securities, residential
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	628,920	346,606
Unrealized Gains	4,387	8,794
Unrealized Losses	(6,879)	(279)
Fair Value	626,428	355,121
Mortgage-backed securities, commercial
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	15,480	17,931
Unrealized Gains	191	559
Unrealized Losses	0	0
Fair Value	15,671	18,490
Collateralized mortgage obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	175,501	209,556
Unrealized Gains	1,272	4,761
Unrealized Losses	(1,768)	(157)
Fair Value	175,005	214,160
State and municipal obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	362,843	285,837
Unrealized Gains	17,833	20,294
Unrealized Losses	(578)	0
Fair Value	380,098	306,131
Municipal taxable
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	38,445	22,440
Unrealized Gains	396	702
Unrealized Losses	(215)	(3)
Fair Value	38,626	23,139
U.S. Treasury
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	205	2,750
Unrealized Gains	0	3
Unrealized Losses	(1)	0
Fair Value	204	2,753
Collateralized debt obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	0	0
Unrealized Gains	3,359	3,136
Unrealized Losses	0	0
Fair Value	3,359	$ 3,136
Other securities
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	5,220
Unrealized Gains	0
Unrealized Losses	0
Fair Value	$ 5,220

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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