INVESTMENT SECURITIES (Schedule of Securities with Unrealized Losses) (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2022 USD ($) item	Dec. 31, 2021 USD ($) item
Held-to-maturity Securities
Number of securities of one issuer \| item	0	0
Impairment loss	$ 0	$ 0
Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	256,987	477,140
Less than 12 Months, Unrealized/Unrecognized Losses	(31,738)	(11,075)
12 months or more, Estimated Fair Value	208,674	53,509
12 months or more, Unrealized/Unrecognized Losses	(30,674)	(1,751)
Total, Estimated Fair Value	465,661	530,649
Total, Unrealized/Unrecognized Losses	(62,412)	(12,826)
Held-to-maturity Securities
Held-to-maturity Securities
Less than 12 Months, Estimated Fair Value	457,917	319,632
Less than 12 Months, Unrealized/Unrecognized Losses	(44,823)	(2,401)
Total, Estimated Fair Value	457,917	319,632
Total, Unrealized Losses	(44,823)	(2,401)
Residential MBS \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	244,366	423,686
Less than 12 Months, Unrealized/Unrecognized Losses	(30,483)	(9,727)
12 months or more, Estimated Fair Value	130,955	12,931
12 months or more, Unrealized/Unrecognized Losses	(21,792)	(738)
Total, Estimated Fair Value	375,321	436,617
Total, Unrealized/Unrecognized Losses	(52,275)	(10,465)
Residential MBS \| Held-to-maturity Securities
Held-to-maturity Securities
Less than 12 Months, Estimated Fair Value	409,189	301,896
Less than 12 Months, Unrealized/Unrecognized Losses	(39,662)	(2,259)
Total, Estimated Fair Value	409,189	301,896
Total, Unrealized Losses	(39,662)	(2,259)
Commercial MBS \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	2,639	11,202
Less than 12 Months, Unrealized/Unrecognized Losses	(26)	(296)
12 months or more, Estimated Fair Value	12,345	3,511
12 months or more, Unrealized/Unrecognized Losses	(1,424)	(83)
Total, Estimated Fair Value	14,984	14,713
Total, Unrealized/Unrecognized Losses	(1,450)	(379)
Commercial MBS \| Held-to-maturity Securities
Held-to-maturity Securities
Less than 12 Months, Estimated Fair Value	7,210	8,039
Less than 12 Months, Unrealized/Unrecognized Losses	(911)	(99)
Total, Estimated Fair Value	7,210	8,039
Total, Unrealized Losses	(911)	(99)
Asset-backed Securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	4,111	4,613
Less than 12 Months, Unrealized/Unrecognized Losses	(213)	(22)
Total, Estimated Fair Value	4,111	4,613
Total, Unrealized/Unrecognized Losses	(213)	(22)
U.S. Government agency securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value		29,267
Less than 12 Months, Unrealized/Unrecognized Losses		(730)
12 months or more, Estimated Fair Value	61,579	37,067
12 months or more, Unrealized/Unrecognized Losses	(6,416)	(930)
Total, Estimated Fair Value	61,579	66,334
Total, Unrealized/Unrecognized Losses	(6,416)	(1,660)
U.S. State and Municipal securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	5,871	8,372
Less than 12 Months, Unrealized/Unrecognized Losses	(1,016)	(300)
12 months or more, Estimated Fair Value	3,795
12 months or more, Unrealized/Unrecognized Losses	(1,042)
Total, Estimated Fair Value	9,666	8,372
Total, Unrealized/Unrecognized Losses	(2,058)	(300)
U.S. State and Municipal securities \| Held-to-maturity Securities
Held-to-maturity Securities
Less than 12 Months, Estimated Fair Value	13,338
Less than 12 Months, Unrealized/Unrecognized Losses	(2,598)
Total, Estimated Fair Value	13,338
Total, Unrealized Losses	(2,598)
US Treasury Securities \| Held-to-maturity Securities
Held-to-maturity Securities
Less than 12 Months, Estimated Fair Value	28,180	9,697
Less than 12 Months, Unrealized/Unrecognized Losses	(1,652)	(43)
Total, Estimated Fair Value	28,180	9,697
Total, Unrealized Losses	$ (1,652)	$ (43)

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