INVESTMENT SECURITIES (Schedule of Securities with Unrealized Losses) (Details) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2021 USD ($) item	Dec. 31, 2020 USD ($) item
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value		$ 37,916
Less than 12 Months, Unrealized/Unrecognized Losses		(81)
Total, Estimated Fair Value		37,916
Total, Unrealized/Unrecognized Losses		$ (81)
Marketable equity securities
Number of securities of one issuer \| item	0	0
Impairment loss	$ 0	$ 0
Equity securities
Marketable equity securities
12 months or more, Estimated Fair Value	2,291
12 months or more, Unrealized/Unrecognized Losses	(23)
Total, Estimated Fair Value	2,291
Total, Unrealized Losses	(23)
Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	416,768	83,964
Less than 12 Months, Unrealized/Unrecognized Losses	(4,066)	(248)
12 months or more, Estimated Fair Value	381	385
12 months or more, Unrealized/Unrecognized Losses	(1)	(1)
Total, Estimated Fair Value	417,149	84,349
Total, Unrealized/Unrecognized Losses	(4,067)	(249)
Residential mortgage-backed securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	321,427	33,734
Less than 12 Months, Unrealized/Unrecognized Losses	(2,911)	(74)
Total, Estimated Fair Value	321,427	33,734
Total, Unrealized/Unrecognized Losses	(2,911)	(74)
Commercial mortgage-backed securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	15,428	12,314
Less than 12 Months, Unrealized/Unrecognized Losses	(199)	(93)
12 months or more, Estimated Fair Value	381	385
12 months or more, Unrealized/Unrecognized Losses	(1)	(1)
Total, Estimated Fair Value	15,809	12,699
Total, Unrealized/Unrecognized Losses	(200)	$ (94)
Asset-backed Securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	4,848
Less than 12 Months, Unrealized/Unrecognized Losses	(32)
Total, Estimated Fair Value	4,848
Total, Unrealized/Unrecognized Losses	(32)
U.S. Government agency securities \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	67,254
Less than 12 Months, Unrealized/Unrecognized Losses	(740)
Total, Estimated Fair Value	67,254
Total, Unrealized/Unrecognized Losses	(740)
Securities issued by states and political subdivisions in the U.S \| Available-for-sale Securities.
Available-for-sale Securities
Less than 12 Months, Estimated Fair Value	7,811
Less than 12 Months, Unrealized/Unrecognized Losses	(184)
Total, Estimated Fair Value	7,811
Total, Unrealized/Unrecognized Losses	(184)
CRA mutual fund \| Equity securities
Marketable equity securities
12 months or more, Estimated Fair Value	2,291
12 months or more, Unrealized/Unrecognized Losses	(23)
Total, Estimated Fair Value	2,291
Total, Unrealized Losses	$ (23)

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