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Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 1,061,181	$ 1,127,057
Securities available for sale, Unrealized Gains	325	338
Securities available for sale, Unrealized Losses	207,291	173,024
Securities available for sale	854,215	954,371
Securities held to maturity, Amortized Cost	154,208	188,980
Securities held to maturity, Unrealized Gains	20	24
Securities held to maturity, Unrealized Losses	17,688	14,816
Securities held to maturity, fair value	136,540	174,188
Allowance for credit losses, Amortized Cost	(4)	(5)
Held-to-maturity securities, net , Amortized Cost	154,204	188,975
U.S. Government Agency And Government Sponsored Enterprises [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	24,535	24,535
Securities available for sale, Unrealized Gains	0	0
Securities available for sale, Unrealized Losses	3,626	3,420
Securities available for sale	20,909	21,115
Securities held to maturity, Amortized Cost	16,476	16,363
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	1,095	848
Securities held to maturity, fair value	15,381	15,515
State And Political Subdivisions [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Amortized Cost	72,666	97,583
Securities held to maturity, Unrealized Gains	20	24
Securities held to maturity, Unrealized Losses	8,374	7,172
Securities held to maturity, fair value	64,312	90,435
Collateralized Mortgage Obligations Government National Mortgage Association Certificates And Obligations Gnma [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Amortized Cost	3,714	4,222
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	368	330
Securities held to maturity, fair value	3,346	3,892
Collateralized Mortgage Obligations Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	11,219	12,175
Securities available for sale, Unrealized Gains	0	0
Securities available for sale, Unrealized Losses	2,773	2,603
Securities available for sale	8,446	9,572
Securities held to maturity, Amortized Cost	12,088	14,268
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	1,165	1,119
Securities held to maturity, fair value	10,923	13,149
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	1,036,646	1,102,522
Securities available for sale, Unrealized Gains	325	338
Securities available for sale, Unrealized Losses	203,665	169,604
Securities available for sale	833,306	933,256
Securities held to maturity, Amortized Cost	65,066	75,034
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	8,219	6,796
Securities held to maturity, fair value	56,847	68,238
Collateralized Mortgage-Backed Securities Government National Mortgage Association Certificates and Obligations (GNMA) [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	109,402	112,202
Securities available for sale, Unrealized Gains	0	1
Securities available for sale, Unrealized Losses	26,410	18,037
Securities available for sale	82,992	94,166
Securities held to maturity, Amortized Cost	20,655	22,541
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	2,806	2,116
Securities held to maturity, fair value	17,849	20,425
Collateralized Mortgage-Backed Securities Federal National Mortgage Association Certificates and Obligations (FNMA) [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	514,062	545,797
Securities available for sale, Unrealized Gains	0	0
Securities available for sale, Unrealized Losses	88,324	76,193
Securities available for sale	425,738	469,604
Securities held to maturity, Amortized Cost	5,942	8,332
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	809	582
Securities held to maturity, fair value	5,133	7,750
Collateralized Mortgage Obligations Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	20,199	21,519
Securities available for sale, Unrealized Gains	0	0
Securities available for sale, Unrealized Losses	5,121	4,163
Securities available for sale	15,078	17,356
Securities held to maturity, Amortized Cost	14,981	17,712
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	1,376	1,253
Securities held to maturity, fair value	13,605	16,459
Collateralized Mortgage Obligations Mortgage-Backed Securities, Issued by Private Enterprises [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	0	0
Securities available for sale, Unrealized Gains	325	337
Securities available for sale, Unrealized Losses	0	0
Securities available for sale	325	337
Collateralized Mortgage-Backed Securities Federal Home Loan Mortgage Corporation Certificates and Obligations (FHLMC) [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	381,764	410,829
Securities available for sale, Unrealized Gains	0	0
Securities available for sale, Unrealized Losses	81,037	68,608
Securities available for sale	300,727	342,221
Securities held to maturity, Amortized Cost	7,686	7,959
Securities held to maturity, Unrealized Gains	0	0
Securities held to maturity, Unrealized Losses	1,695	1,396
Securities held to maturity, fair value	$ 5,991	$ 6,563

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