Investment Securities (Amortized Cost And Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule of Debt Securities Available For Sale and Held To Maturity Securities [Line Item]
Securities available for sale, Amortized Cost	$ 389,845	$ 455,582
Securities available for sale, Unrealized Gains	6,528	845
Securities available for sale, Unrealized Losses	932	10,750
Securities available for sale	395,441	445,677
Securities held to maturity, Amortized Cost	386,305	446,581
Securities held to maturity, Unrealized Gains	4,942	899
Securities held to maturity, Unrealized Losses	761	7,899
Securities held to maturity, fair value	390,486	439,581
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	71,522	155,102
Securities available for sale, Unrealized Gains	1,288
Securities available for sale, Unrealized Losses	14	3,074
Securities available for sale	72,796	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	197,743	234,845
Securities held to maturity, Unrealized Gains	3,529	876
Securities held to maturity, Unrealized Losses	5	1,211
Securities held to maturity, fair value	201,267	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	9,269	133
Securities available for sale, Unrealized Losses	34
Securities available for sale	9,235	133
Securities held to maturity, Amortized Cost	53,179	62,103
Securities held to maturity, Unrealized Gains	228	1
Securities held to maturity, Unrealized Losses	330	2,179
Securities held to maturity, fair value	53,077	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	5,016	37
Securities available for sale, Unrealized Losses	17
Securities available for sale	4,999	37
Securities held to maturity, Amortized Cost	67,548	78,200
Securities held to maturity, Unrealized Gains	444
Securities held to maturity, Unrealized Losses	261	2,597
Securities held to maturity, fair value	67,731	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	14,905	17,798
Securities held to maturity, Unrealized Gains	42
Securities held to maturity, Unrealized Losses	98	535
Securities held to maturity, fair value	14,849	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	658	767
Securities available for sale	658	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	318,323	300,480
Securities available for sale, Unrealized Gains	5,240	845
Securities available for sale, Unrealized Losses	918	7,676
Securities available for sale	322,645	293,649
Securities held to maturity, Amortized Cost	188,562	211,736
Securities held to maturity, Unrealized Gains	1,413	23
Securities held to maturity, Unrealized Losses	756	6,688
Securities held to maturity, fair value	189,219	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	264,435	258,984
Securities available for sale, Unrealized Gains	4,100	44
Securities available for sale, Unrealized Losses	688	6,325
Securities available for sale	267,847	252,703
Securities held to maturity, Amortized Cost	10,798	11,602
Securities held to maturity, Unrealized Gains	229	8
Securities held to maturity, Unrealized Losses	1	261
Securities held to maturity, fair value	11,026	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	35,080	35,962
Securities available for sale, Unrealized Gains	412	13
Securities available for sale, Unrealized Losses	179	1,275
Securities available for sale	35,313	34,700
Securities held to maturity, Amortized Cost	4,048	4,583
Securities held to maturity, Unrealized Gains	95
Securities held to maturity, Unrealized Losses	26	193
Securities held to maturity, fair value	4,117	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	4,523	5,364
Securities available for sale, Unrealized Gains	70	21
Securities available for sale, Unrealized Losses		76
Securities available for sale	4,593	5,309
Securities held to maturity, Amortized Cost	38,084	37,450
Securities held to maturity, Unrealized Gains	375	14
Securities held to maturity, Unrealized Losses	40	923
Securities held to maturity, fair value	$ 38,419	$ 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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