INVESTMENT SECURITIES, Amortized Cost, Unrealized Gains and Losses and Estimated Fair Values of Investments in Debt and Other Securities (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Investment securities available-for-sale [Abstract]
Amortized cost	$ 608,472		$ 620,314
Unrealized gains	352		733
Unrealized losses	(50,383)		(48,690)
Estimated fair value	558,441		572,357
ACL	0		0
Proceeds from sales of available-for-sale securities	971	$ 7,201
Gross realized gains from sales of available-for-sale securities	0	58
Gross realized losses from sales of available-for-sale securities	42	$ 56
U.S. Treasury Securities [Member]
Investment securities available-for-sale [Abstract]
Amortized cost	84,676		90,063
Unrealized gains	60		134
Unrealized losses	(2,850)		(3,015)
Estimated fair value	81,886		87,182
ACL	0		0
Securities of U.S. Government Agencies and Corporations [Member]
Investment securities available-for-sale [Abstract]
Amortized cost	115,840		121,305
Unrealized gains	48		105
Unrealized losses	(6,177)		(6,331)
Estimated fair value	109,711		115,079
ACL	0		0
Obligations of States and Political Subdivisions [Member]
Investment securities available-for-sale [Abstract]
Amortized cost	55,599		55,021
Unrealized gains	149		237
Unrealized losses	(3,860)		(3,581)
Estimated fair value	51,888		51,677
ACL	0		0
Collateralized Mortgage Obligations [Member]
Investment securities available-for-sale [Abstract]
Amortized cost	105,134		107,658
Unrealized gains	0		15
Unrealized losses	(17,681)		(16,726)
Estimated fair value	87,453		90,947
ACL	0		0
Mortgage-backed Securities [Member]
Investment securities available-for-sale [Abstract]
Amortized cost	247,223		246,267
Unrealized gains	95		242
Unrealized losses	(19,815)		(19,037)
Estimated fair value	227,503		227,472
ACL	$ 0		$ 0