Investment Securities (Investments Gross Unrealized Losses And Fair Value) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	$ 251	$ 319,678
Securities available for sale, Less than 12 months, Unrealized Losses	1	2,618
Securities available for sale, 12 months or longer, Fair Value	438,290	115,552
Securities available for sale, 12 months or longer, Unrealized Losses	10,749	2,548
Securities available for sale, Fair Value, Total	438,541	435,230
Securities available for sale, Unrealized Losses, Total	10,750	5,166
Securities held to maturity, Less than 12 months, Fair Value	50,519	113,419
Securities held to maturity, Less than 12 months, Unrealized Losses	181	1,339
Securities held to maturity, 12 months or longer, Fair Value	234,507	159,211
Securities held to maturity, 12 months or longer, Unrealized Losses	7,718	4,485
Securities held to maturity, Fair Value, Total	285,026	272,630
Securities held to maturity, Unrealized Losses, Total	7,899	5,824
Total Securities, Less than 12 months, Fair Value	50,770	433,097
Total Securities, Less than 12 months, Unrealized Losses	182	3,957
Total Securities, 12 months or longer, Fair Value	672,797	274,763
Total Securities, 12 months or longer, Unrealized Losses	18,467	7,033
Total Securities, Fair Value	723,567	707,860
Total Securities, Unrealized Losses	18,649	10,990
U.S. Government Agencies And Government Sponsored Enterprises [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value		95,046
Securities available for sale, Less than 12 months, Unrealized Losses		571
Securities available for sale, 12 months or longer, Fair Value	152,028	31,561
Securities available for sale, 12 months or longer, Unrealized Losses	3,074	687
Securities available for sale, Fair Value, Total	152,028	126,607
Securities available for sale, Unrealized Losses, Total	3,074	1,258
State And Political Subdivisions [Member]
Investment [Line Items]
Securities held to maturity, Less than 12 months, Fair Value	35,751	36,368
Securities held to maturity, Less than 12 months, Unrealized Losses	91	295
Securities held to maturity, 12 months or longer, Fair Value	49,534	14,492
Securities held to maturity, 12 months or longer, Unrealized Losses	1,120	367
Securities held to maturity, Fair Value, Total	85,285	50,860
Securities held to maturity, Unrealized Losses, Total	1,211	662
Collateralized Mortgage Obligations [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, 12 months or longer, Fair Value	56	119
Securities available for sale, 12 months or longer, Unrealized Losses		1
Securities available for sale, Fair Value, Total	56	119
Securities available for sale, Unrealized Losses, Total		1
Securities held to maturity, Less than 12 months, Fair Value		16,830
Securities held to maturity, Less than 12 months, Unrealized Losses		202
Securities held to maturity, 12 months or longer, Fair Value	57,973	57,645
Securities held to maturity, 12 months or longer, Unrealized Losses	2,179	1,756
Securities held to maturity, Fair Value, Total	57,973	74,475
Securities held to maturity, Unrealized Losses, Total	2,179	1,958
Collateralized Mortgage Obligations [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, 12 months or longer, Fair Value	6	8
Securities available for sale, Fair Value, Total	6	8
Securities held to maturity, Less than 12 months, Fair Value		23,727
Securities held to maturity, Less than 12 months, Unrealized Losses		337
Securities held to maturity, 12 months or longer, Fair Value	75,603	66,467
Securities held to maturity, 12 months or longer, Unrealized Losses	2,597	1,828
Securities held to maturity, Fair Value, Total	75,603	90,194
Securities held to maturity, Unrealized Losses, Total	2,597	2,165
Collateralized Mortgage Obligations [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
Securities held to maturity, Less than 12 months, Fair Value		15,401
Securities held to maturity, Less than 12 months, Unrealized Losses		340
Securities held to maturity, 12 months or longer, Fair Value	17,263	5,635
Securities held to maturity, 12 months or longer, Unrealized Losses	535	162
Securities held to maturity, Fair Value, Total	17,263	21,036
Securities held to maturity, Unrealized Losses, Total	535	502
Mortgage-Backed Securities [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	251	224,632
Securities available for sale, Less than 12 months, Unrealized Losses	1	2,047
Securities available for sale, 12 months or longer, Fair Value	286,262	83,991
Securities available for sale, 12 months or longer, Unrealized Losses	7,675	1,861
Securities available for sale, Fair Value, Total	286,513	308,623
Securities available for sale, Unrealized Losses, Total	7,676	3,908
Securities held to maturity, Less than 12 months, Fair Value	14,768	77,051
Securities held to maturity, Less than 12 months, Unrealized Losses	90	1,044
Securities held to maturity, 12 months or longer, Fair Value	184,973	144,719
Securities held to maturity, 12 months or longer, Unrealized Losses	6,598	4,118
Securities held to maturity, Fair Value, Total	199,741	221,770
Securities held to maturity, Unrealized Losses, Total	6,688	5,162
Mortgage-Backed Securities [Member] \| Federal National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value	251	201,754
Securities available for sale, Less than 12 months, Unrealized Losses	1	1,855
Securities available for sale, 12 months or longer, Fair Value	247,615	67,383
Securities available for sale, 12 months or longer, Unrealized Losses	6,324	1,365
Securities available for sale, Fair Value, Total	247,866	269,137
Securities available for sale, Unrealized Losses, Total	6,325	3,220
Securities held to maturity, Less than 12 months, Fair Value	1,518	3,766
Securities held to maturity, Less than 12 months, Unrealized Losses	3	29
Securities held to maturity, 12 months or longer, Fair Value	8,695	2,694
Securities held to maturity, 12 months or longer, Unrealized Losses	258	59
Securities held to maturity, Fair Value, Total	10,213	6,460
Securities held to maturity, Unrealized Losses, Total	261	88
Mortgage-Backed Securities [Member] \| Federal Home Loan Mortgage Corporation [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value		20,446
Securities available for sale, Less than 12 months, Unrealized Losses		192
Securities available for sale, 12 months or longer, Fair Value	33,918	15,601
Securities available for sale, 12 months or longer, Unrealized Losses	1,275	483
Securities available for sale, Fair Value, Total	33,918	36,047
Securities available for sale, Unrealized Losses, Total	1,275	675
Securities held to maturity, Less than 12 months, Fair Value	1,467
Securities held to maturity, Less than 12 months, Unrealized Losses	5
Securities held to maturity, 12 months or longer, Fair Value	2,923	3,094
Securities held to maturity, 12 months or longer, Unrealized Losses	188	119
Securities held to maturity, Fair Value, Total	4,390	3,094
Securities held to maturity, Unrealized Losses, Total	193	119
Mortgage-Backed Securities [Member] \| Government National Mortgage Association [Member]
Investment [Line Items]
Securities available for sale, Less than 12 months, Fair Value		2,432
Securities available for sale, 12 months or longer, Fair Value	4,667	880
Securities available for sale, 12 months or longer, Unrealized Losses	76	12
Securities available for sale, Fair Value, Total	4,667	3,312
Securities available for sale, Unrealized Losses, Total	76	12
Securities held to maturity, Less than 12 months, Fair Value	11,783	17,327
Securities held to maturity, Less than 12 months, Unrealized Losses	82	136
Securities held to maturity, 12 months or longer, Fair Value	22,516	9,184
Securities held to maturity, 12 months or longer, Unrealized Losses	841	194
Securities held to maturity, Fair Value, Total	34,299	26,511
Securities held to maturity, Unrealized Losses, Total	$ 923	$ 330

Amount of accumulated pre-tax unrealized loss on securities.

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Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months.

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