Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 607,665	$ 415,852
Securities available for sale, Unrealized Gains	20,462	3,696
Securities available for sale, Unrealized Losses	68	1,631
Securities available for sale	628,059	417,917
Securities held to maturity, Amortized Cost	271,973	359,000
Securities held to maturity, Unrealized Gains	10,062	4,882
Securities held to maturity, Unrealized Losses		623
Securities held to maturity, fair value	282,035	363,259
Allowance for credit losses, Amortized Cost	(7)
Held-to-maturity securities, net , Amortized Cost	271,966	359,000
U.S. Government Agencies 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	6,239	26,440
Securities available for sale, Unrealized Gains	396	437
Securities available for sale	6,635	26,877
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	144,506	192,215
Securities held to maturity, Unrealized Gains	4,478	3,803
Securities held to maturity, fair value	148,984	196,018
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	3,047	23,834
Securities available for sale, Unrealized Gains	97
Securities available for sale, Unrealized Losses		57
Securities available for sale	3,144	23,777
Securities held to maturity, Amortized Cost	29,988	41,561
Securities held to maturity, Unrealized Gains	1,075	150
Securities held to maturity, Unrealized Losses		256
Securities held to maturity, fair value	31,063	41,455
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		4,907
Securities available for sale, Unrealized Losses		18
Securities available for sale		4,889
Securities held to maturity, Amortized Cost	35,897	49,389
Securities held to maturity, Unrealized Gains	1,581	307
Securities held to maturity, Unrealized Losses		103
Securities held to maturity, fair value	37,478	49,593
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	7,864	11,033
Securities held to maturity, Unrealized Gains	265	12
Securities held to maturity, Unrealized Losses		83
Securities held to maturity, fair value	8,129	10,962
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	435	618
Securities available for sale	435	618
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	601,426	389,412
Securities available for sale, Unrealized Gains	20,066	3,259
Securities available for sale, Unrealized Losses	68	1,631
Securities available for sale	621,424	391,040
Securities held to maturity, Amortized Cost	127,467	166,785
Securities held to maturity, Unrealized Gains	5,584	1,079
Securities held to maturity, Unrealized Losses		623
Securities held to maturity, fair value	133,051	167,241
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	350,627	293,873
Securities available for sale, Unrealized Gains	15,549	2,263
Securities available for sale, Unrealized Losses	44	1,380
Securities available for sale	366,132	294,756
Securities held to maturity, Amortized Cost	10,776	12,049
Securities held to maturity, Unrealized Gains	703	227
Securities held to maturity, Unrealized Losses		6
Securities held to maturity, fair value	11,479	12,270
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	225,645	52,733
Securities available for sale, Unrealized Gains	3,155	318
Securities available for sale, Unrealized Losses	24	172
Securities available for sale	228,776	52,879
Securities held to maturity, Amortized Cost	5,858	6,995
Securities held to maturity, Unrealized Gains	382	77
Securities held to maturity, Unrealized Losses		47
Securities held to maturity, fair value	6,240	7,025
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	22,107	14,065
Securities available for sale, Unrealized Gains	830	60
Securities available for sale, Unrealized Losses		4
Securities available for sale	22,937	14,121
Securities held to maturity, Amortized Cost	37,084	45,758
Securities held to maturity, Unrealized Gains	1,578	306
Securities held to maturity, Unrealized Losses		128
Securities held to maturity, fair value	$ 38,662	$ 45,936

Allowance for credit losses, amortized cost.

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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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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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