Investment Securities (Amortization Cost And Estimated Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost		$ 5,504
Held-to-Maturity Securities, Gross Unrealized Gains		48
Held-to-Maturity Securities, Fair Value		5,552
Available-for-Sale Securities, Amortized Cost	$ 687,631	762,244
Available-for-Sale Securities, Gross Unrealized Gains	13,620	4,130
Available-for-Sale Securities, Gross Unrealized Losses	(3,707)	(8,359)
Available-for-Sale Securities, Fair value	697,544	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	(3,170)	(1,410)
Available-for-Sale Securities, Fair value	115,830	117,590
State And Municipals [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost		5,142
Held-to-Maturity Securities, Gross Unrealized Gains		36
Held-to-Maturity Securities, Fair Value		5,178
Available-for-Sale Securities, Amortized Cost	372,113	422,235
Available-for-Sale Securities, Gross Unrealized Gains	10,269	3,220
Available-for-Sale Securities, Gross Unrealized Losses	(239)	(5,417)
Available-for-Sale Securities, Fair value	382,143	420,038
Pass-Through Mortgage Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost		267
Held-to-Maturity Securities, Gross Unrealized Gains		11
Held-to-Maturity Securities, Fair Value		278
Available-for-Sale Securities, Amortized Cost	60,307	66,631
Available-for-Sale Securities, Gross Unrealized Gains	1,104	24
Available-for-Sale Securities, Gross Unrealized Losses	(39)	(1,169)
Available-for-Sale Securities, Fair value	61,372	65,486
Collateralized Mortgage Obligations [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost		95
Held-to-Maturity Securities, Gross Unrealized Gains		1
Held-to-Maturity Securities, Fair Value		96
Available-for-Sale Securities, Amortized Cost	136,211	154,378
Available-for-Sale Securities, Gross Unrealized Gains	2,247	886
Available-for-Sale Securities, Gross Unrealized Losses	(259)	(363)
Available-for-Sale Securities, Fair value	$ 138,199	$ 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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