Investment Securities (Amortized Cost And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 415,852	$ 455,582
Securities available for sale, Unrealized Gains	3,696	845
Securities available for sale, Unrealized Losses	1,631	10,750
Securities available for sale	417,917	445,677
Securities held to maturity, Amortized Cost	359,000	446,581
Securities held to maturity, Unrealized Gains	4,882	899
Securities held to maturity, Unrealized Losses	623	7,899
Securities held to maturity, fair value	363,259	439,581
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	26,440	155,102
Securities available for sale, Unrealized Gains	437
Securities available for sale, Unrealized Losses		3,074
Securities available for sale	26,877	152,028
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	192,215	234,845
Securities held to maturity, Unrealized Gains	3,803	876
Securities held to maturity, Unrealized Losses		1,211
Securities held to maturity, fair value	196,018	234,510
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	23,834	133
Securities available for sale, Unrealized Losses	57
Securities available for sale	23,777	133
Securities held to maturity, Amortized Cost	41,561	62,103
Securities held to maturity, Unrealized Gains	150	1
Securities held to maturity, Unrealized Losses	256	2,179
Securities held to maturity, fair value	41,455	59,925
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	37
Securities available for sale, Unrealized Losses	18
Securities available for sale	4,889	37
Securities held to maturity, Amortized Cost	49,389	78,200
Securities held to maturity, Unrealized Gains	307
Securities held to maturity, Unrealized Losses	103	2,597
Securities held to maturity, fair value	49,593	75,603
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	11,033	17,798
Securities held to maturity, Unrealized Gains	12
Securities held to maturity, Unrealized Losses	83	535
Securities held to maturity, fair value	10,962	17,263
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	618	767
Securities available for sale	618	767
Mortgage-Backed Securities [Member]
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	389,412	300,480
Securities available for sale, Unrealized Gains	3,259	845
Securities available for sale, Unrealized Losses	1,631	7,676
Securities available for sale	391,040	293,649
Securities held to maturity, Amortized Cost	166,785	211,736
Securities held to maturity, Unrealized Gains	1,079	23
Securities held to maturity, Unrealized Losses	623	6,688
Securities held to maturity, fair value	167,241	205,071
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	293,873	258,984
Securities available for sale, Unrealized Gains	2,263	44
Securities available for sale, Unrealized Losses	1,380	6,325
Securities available for sale	294,756	252,703
Securities held to maturity, Amortized Cost	12,049	11,602
Securities held to maturity, Unrealized Gains	227	8
Securities held to maturity, Unrealized Losses	6	261
Securities held to maturity, fair value	12,270	11,349
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	52,733	35,962
Securities available for sale, Unrealized Gains	318	13
Securities available for sale, Unrealized Losses	172	1,275
Securities available for sale	52,879	34,700
Securities held to maturity, Amortized Cost	6,995	4,583
Securities held to maturity, Unrealized Gains	77
Securities held to maturity, Unrealized Losses	47	193
Securities held to maturity, fair value	7,025	4,390
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	14,065	5,364
Securities available for sale, Unrealized Gains	60	21
Securities available for sale, Unrealized Losses	4	76
Securities available for sale	14,121	5,309
Securities held to maturity, Amortized Cost	45,758	37,450
Securities held to maturity, Unrealized Gains	306	14
Securities held to maturity, Unrealized Losses	128	923
Securities held to maturity, fair value	$ 45,936	$ 36,541

Debt securities available for sale and held to maturity securities.

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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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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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