Investment Securities (Amortization Cost And Estimated Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	$ 5,504	$ 7,636
Held-to-Maturity Securities, Gross Unrealized Gains	48	113
Held-to-Maturity Securities, Fair Value	5,552	7,749
Available-for-Sale Securities, Amortized Cost	762,244	715,872
Available-for-Sale Securities, Gross Unrealized Gains	4,130	10,150
Available-for-Sale Securities, Gross Unrealized Losses	(8,359)	(5,894)
Available-for-Sale Securities, Fair value	758,015	720,128
Corporate Bonds [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Available-for-Sale Securities, Amortized Cost	119,000
Available-for-Sale Securities, Gross Unrealized Losses	(1,410)
Available-for-Sale Securities, Fair value	117,590
State And Municipals [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	5,142	6,970
Held-to-Maturity Securities, Gross Unrealized Gains	36	78
Held-to-Maturity Securities, Fair Value	5,178	7,048
Available-for-Sale Securities, Amortized Cost	422,235	453,158
Available-for-Sale Securities, Gross Unrealized Gains	3,220	10,051
Available-for-Sale Securities, Gross Unrealized Losses	(5,417)	(1,886)
Available-for-Sale Securities, Fair value	420,038	461,323
Pass-Through Mortgage Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	267	311
Held-to-Maturity Securities, Gross Unrealized Gains	11	21
Held-to-Maturity Securities, Fair Value	278	332
Available-for-Sale Securities, Amortized Cost	66,631	72,539
Available-for-Sale Securities, Gross Unrealized Gains	24	84
Available-for-Sale Securities, Gross Unrealized Losses	(1,169)	(1,232)
Available-for-Sale Securities, Fair value	65,486	71,391
Collateralized Mortgage Obligations [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	95	355
Held-to-Maturity Securities, Gross Unrealized Gains	1	14
Held-to-Maturity Securities, Fair Value	96	369
Available-for-Sale Securities, Amortized Cost	154,378	190,175
Available-for-Sale Securities, Gross Unrealized Gains	886	15
Available-for-Sale Securities, Gross Unrealized Losses	(363)	(2,776)
Available-for-Sale Securities, Fair value	$ 154,901	$ 187,414

Schedule Of Amortized Cost And Estimated Fair Values [Line Items]

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in equity securities classified as available-for-sale.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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

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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

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

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