Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 752,531	$ 607,665
Securities available for sale, Unrealized Gains	11,400	20,462
Securities available for sale, Unrealized Losses	10,442	68
Securities available for sale	753,489	628,059
Securities held to maturity, Amortized Cost	256,134	271,973
Securities held to maturity, Unrealized Gains	8,195	10,062
Securities held to maturity, fair value	264,329	282,035
Allowance for credit losses, Amortized Cost	(7)	(7)
Held-to-maturity securities, net , Amortized Cost	256,127	271,966
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	16,244	6,239
Securities available for sale, Unrealized Gains	348	396
Securities available for sale, Unrealized Losses	59
Securities available for sale	16,533	6,635
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	139,264	144,506
Securities held to maturity, Unrealized Gains	3,767	4,478
Securities held to maturity, fair value	143,031	148,984
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	22,361	3,047
Securities available for sale, Unrealized Gains	89	97
Securities available for sale, Unrealized Losses	43
Securities available for sale	22,407	3,144
Securities held to maturity, Amortized Cost	27,230	29,988
Securities held to maturity, Unrealized Gains	920	1,075
Securities held to maturity, fair value	28,150	31,063
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	6,943
Securities available for sale, Unrealized Losses	22
Securities available for sale	6,921
Securities held to maturity, Amortized Cost	32,206	35,897
Securities held to maturity, Unrealized Gains	1,242	1,581
Securities held to maturity, fair value	33,448	37,478
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities held to maturity, Amortized Cost	7,198	7,864
Securities held to maturity, Unrealized Gains	238	265
Securities held to maturity, fair value	7,436	8,129
Collateralized Mortgage Obligations [Member] \| Privately Issued [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Unrealized Gains	431	435
Securities available for sale	431	435
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	736,287	601,426
Securities available for sale, Unrealized Gains	11,052	20,066
Securities available for sale, Unrealized Losses	10,383	68
Securities available for sale	736,956	621,424
Securities held to maturity, Amortized Cost	116,870	127,467
Securities held to maturity, Unrealized Gains	4,428	5,584
Securities held to maturity, fair value	121,298	133,051
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	435,287	350,627
Securities available for sale, Unrealized Gains	8,798	15,549
Securities available for sale, Unrealized Losses	4,432	44
Securities available for sale	439,653	366,132
Securities held to maturity, Amortized Cost	10,147	10,776
Securities held to maturity, Unrealized Gains	522	703
Securities held to maturity, fair value	10,669	11,479
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	250,091	225,645
Securities available for sale, Unrealized Gains	1,239	3,155
Securities available for sale, Unrealized Losses	5,760	24
Securities available for sale	245,570	228,776
Securities held to maturity, Amortized Cost	5,521	5,858
Securities held to maturity, Unrealized Gains	193	382
Securities held to maturity, fair value	5,714	6,240
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	21,605	22,107
Securities available for sale, Unrealized Gains	495	830
Securities available for sale, Unrealized Losses	126
Securities available for sale	21,974	22,937
Securities held to maturity, Amortized Cost	34,568	37,084
Securities held to maturity, Unrealized Gains	1,313	1,578
Securities held to maturity, fair value	$ 35,881	$ 38,662

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Debt securities available for sale and held to maturity securities.

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Held-to-maturity securities, net.

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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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Amount, before tax, of unrealized loss 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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Amortized cost of 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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