Investment Securities (Amortization Cost And Estimated Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	$ 3,983	$ 5,504
Held-to-Maturity Securities, Gross Unrealized Gains	40	48
Held-to-Maturity Securities, Fair Value	4,023	5,552
Available-for-Sale Securities, Amortized Cost	716,245	762,244
Available-for-Sale Securities, Gross Unrealized Gains	15,140	4,130
Available-for-Sale Securities, Gross Unrealized Losses	(2,890)	(8,359)
Available-for-Sale Securities, Fair value	728,495	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	(2,575)	(1,410)
Available-for-Sale Securities, Fair value	116,425	117,590
U.S. Treasury Bills [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Available-for-Sale Securities, Amortized Cost	12,493
Available-for-Sale Securities, Gross Unrealized Gains	2
Available-for-Sale Securities, Fair value	12,495
State And Municipals [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	3,737	5,142
Held-to-Maturity Securities, Gross Unrealized Gains	24	36
Held-to-Maturity Securities, Fair Value	3,761	5,178
Available-for-Sale Securities, Amortized Cost	380,556	422,235
Available-for-Sale Securities, Gross Unrealized Gains	10,796	3,220
Available-for-Sale Securities, Gross Unrealized Losses	(187)	(5,417)
Available-for-Sale Securities, Fair value	391,165	420,038
Pass-Through Mortgage Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	246	267
Held-to-Maturity Securities, Gross Unrealized Gains	16	11
Held-to-Maturity Securities, Fair Value	262	278
Available-for-Sale Securities, Amortized Cost	61,222	66,631
Available-for-Sale Securities, Gross Unrealized Gains	1,212	24
Available-for-Sale Securities, Gross Unrealized Losses	(22)	(1,169)
Available-for-Sale Securities, Fair value	62,412	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	142,974	154,378
Available-for-Sale Securities, Gross Unrealized Gains	3,130	886
Available-for-Sale Securities, Gross Unrealized Losses	(106)	(363)
Available-for-Sale Securities, Fair value	$ 145,998	$ 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 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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