Investment Securities (Amortized Cost and Fair Value of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 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	$ 426,550	$ 415,852
Securities available for sale, Unrealized Gains	18,761	3,696
Securities available for sale, Unrealized Losses	466	1,631
Securities available for sale	444,845	417,917
Securities held to maturity, Amortized Cost	346,252	359,000
Securities held to maturity, Unrealized Gains	8,322	4,882
Securities held to maturity, Unrealized Losses	3	623
Securities held to maturity, fair value	354,571	363,259
Allowance for credit losses, Amortized Cost	(13)
Held-to-maturity securities, net , Amortized Cost	346,239	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	9,587	26,440
Securities available for sale, Unrealized Gains	492	437
Securities available for sale	10,079	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	187,401	192,215
Securities held to maturity, Unrealized Gains	2,797	3,803
Securities held to maturity, Unrealized Losses	3
Securities held to maturity, fair value	190,195	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	23,182	23,834
Securities available for sale, Unrealized Gains	530
Securities available for sale, Unrealized Losses	36	57
Securities available for sale	23,676	23,777
Securities held to maturity, Amortized Cost	39,216	41,561
Securities held to maturity, Unrealized Gains	1,263	150
Securities held to maturity, Unrealized Losses		256
Securities held to maturity, fair value	40,479	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	4,808	4,907
Securities available for sale, Unrealized Losses	48	18
Securities available for sale	4,760	4,889
Securities held to maturity, Amortized Cost	46,854	49,389
Securities held to maturity, Unrealized Gains	1,855	307
Securities held to maturity, Unrealized Losses		103
Securities held to maturity, fair value	48,709	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	10,443	11,033
Securities held to maturity, Unrealized Gains	319	12
Securities held to maturity, Unrealized Losses		83
Securities held to maturity, fair value	10,762	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	502	618
Securities available for sale	502	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	416,963	389,412
Securities available for sale, Unrealized Gains	18,269	3,259
Securities available for sale, Unrealized Losses	466	1,631
Securities available for sale	434,766	391,040
Securities held to maturity, Amortized Cost	158,851	166,785
Securities held to maturity, Unrealized Gains	5,525	1,079
Securities held to maturity, Unrealized Losses		623
Securities held to maturity, fair value	164,376	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	284,725	293,873
Securities available for sale, Unrealized Gains	14,302	2,263
Securities available for sale, Unrealized Losses	217	1,380
Securities available for sale	298,810	294,756
Securities held to maturity, Amortized Cost	11,908	12,049
Securities held to maturity, Unrealized Gains	530	227
Securities held to maturity, Unrealized Losses		6
Securities held to maturity, fair value	12,438	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	83,977	52,733
Securities available for sale, Unrealized Gains	2,597	318
Securities available for sale, Unrealized Losses		172
Securities available for sale	86,574	52,879
Securities held to maturity, Amortized Cost	6,703	6,995
Securities held to maturity, Unrealized Gains	245	77
Securities held to maturity, Unrealized Losses		47
Securities held to maturity, fair value	6,948	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	20,271	14,065
Securities available for sale, Unrealized Gains	338	60
Securities available for sale, Unrealized Losses	165	4
Securities available for sale	20,444	14,121
Securities held to maturity, Amortized Cost	43,727	45,758
Securities held to maturity, Unrealized Gains	1,313	306
Securities held to maturity, Unrealized Losses		128
Securities held to maturity, fair value	$ 45,040	$ 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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