Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 495,618	$ 415,852
Securities available for sale, Unrealized Gains	20,559	3,696
Securities available for sale, Unrealized Losses	206	1,631
Securities available for sale	515,971	417,917
Securities held to maturity, Amortized Cost	290,954	359,000
Securities held to maturity, Unrealized Gains	10,924	4,882
Securities held to maturity, Unrealized Losses		623
Securities held to maturity, fair value	301,878	363,259
Allowance for credit losses, Amortized Cost	(8)
Held-to-maturity securities, net , Amortized Cost	290,946	359,000
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	6,234	26,440
Securities available for sale, Unrealized Gains	421	437
Securities available for sale	6,655	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	151,611	192,215
Securities held to maturity, Unrealized Gains	5,052	3,803
Securities held to maturity, fair value	156,663	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	18,104	23,834
Securities available for sale, Unrealized Gains	229
Securities available for sale, Unrealized Losses		57
Securities available for sale	18,333	23,777
Securities held to maturity, Amortized Cost	33,396	41,561
Securities held to maturity, Unrealized Gains	1,236	150
Securities held to maturity, Unrealized Losses		256
Securities held to maturity, fair value	34,632	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	4,365	4,907
Securities available for sale, Unrealized Gains	16
Securities available for sale, Unrealized Losses		18
Securities available for sale	4,381	4,889
Securities held to maturity, Amortized Cost	39,905	49,389
Securities held to maturity, Unrealized Gains	1,835	307
Securities held to maturity, Unrealized Losses		103
Securities held to maturity, fair value	41,740	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	8,652	11,033
Securities held to maturity, Unrealized Gains	309	12
Securities held to maturity, Unrealized Losses		83
Securities held to maturity, fair value	8,961	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	489,384	389,412
Securities available for sale, Unrealized Gains	20,138	3,259
Securities available for sale, Unrealized Losses	206	1,631
Securities available for sale	509,316	391,040
Securities held to maturity, Amortized Cost	139,343	166,785
Securities held to maturity, Unrealized Gains	5,872	1,079
Securities held to maturity, Unrealized Losses		623
Securities held to maturity, fair value	145,215	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	303,740	293,873
Securities available for sale, Unrealized Gains	15,923	2,263
Securities available for sale, Unrealized Losses	66	1,380
Securities available for sale	319,597	294,756
Securities held to maturity, Amortized Cost	11,576	12,049
Securities held to maturity, Unrealized Gains	725	227
Securities held to maturity, Unrealized Losses		6
Securities held to maturity, fair value	12,301	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	139,875	52,733
Securities available for sale, Unrealized Gains	2,684	318
Securities available for sale, Unrealized Losses	140	172
Securities available for sale	142,419	52,879
Securities held to maturity, Amortized Cost	6,183	6,995
Securities held to maturity, Unrealized Gains	365	77
Securities held to maturity, Unrealized Losses		47
Securities held to maturity, fair value	6,548	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	23,300	14,065
Securities available for sale, Unrealized Gains	851	60
Securities available for sale, Unrealized Losses		4
Securities available for sale	24,151	14,121
Securities held to maturity, Amortized Cost	39,631	45,758
Securities held to maturity, Unrealized Gains	1,402	306
Securities held to maturity, Unrealized Losses		128
Securities held to maturity, fair value	$ 41,033	$ 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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