Investment Securities (Amortization Cost And Estimated Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	$ 5,124	$ 5,504
Held-to-Maturity Securities, Gross Unrealized Gains	48	48
Held-to-Maturity Securities, Fair Value	5,172	5,552
Available-for-Sale Securities, Amortized Cost	745,733	762,244
Available-for-Sale Securities, Gross Unrealized Gains	7,971	4,130
Available-for-Sale Securities, Gross Unrealized Losses	(3,783)	(8,359)
Available-for-Sale Securities, Fair value	749,921	758,015
Corporate Bonds [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Available-for-Sale Securities, Amortized Cost	119,000	119,000
Available-for-Sale Securities, Gross Unrealized Losses	(1,270)	(1,410)
Available-for-Sale Securities, Fair value	117,730	117,590
State And Municipals [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	4,809	5,142
Held-to-Maturity Securities, Gross Unrealized Gains	35	36
Held-to-Maturity Securities, Fair Value	4,844	5,178
Available-for-Sale Securities, Amortized Cost	408,205	422,235
Available-for-Sale Securities, Gross Unrealized Gains	5,932	3,220
Available-for-Sale Securities, Gross Unrealized Losses	(1,792)	(5,417)
Available-for-Sale Securities, Fair value	412,345	420,038
Pass-Through Mortgage Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	260	267
Held-to-Maturity Securities, Gross Unrealized Gains	13	11
Held-to-Maturity Securities, Fair Value	273	278
Available-for-Sale Securities, Amortized Cost	66,833	66,631
Available-for-Sale Securities, Gross Unrealized Gains	284	24
Available-for-Sale Securities, Gross Unrealized Losses	(558)	(1,169)
Available-for-Sale Securities, Fair value	66,559	65,486
Collateralized Mortgage Obligations [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	55	95
Held-to-Maturity Securities, Gross Unrealized Gains		1
Held-to-Maturity Securities, Fair Value	55	96
Available-for-Sale Securities, Amortized Cost	151,695	154,378
Available-for-Sale Securities, Gross Unrealized Gains	1,755	886
Available-for-Sale Securities, Gross Unrealized Losses	(163)	(363)
Available-for-Sale Securities, Fair value	$ 153,287	$ 154,901

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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