Investment Securities (Amortization Cost And Estimated Fair Value Of Investment Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	$ 5,575	$ 7,636
Held-to-Maturity Securities, Gross Unrealized Gains	78	113
Held-to-Maturity Securities, Fair Value	5,653	7,749
Available-for-Sale Securities, Amortized Cost	812,431	715,872
Available-for-Sale Securities, Gross Unrealized Gains	4,857	10,150
Available-for-Sale Securities, Gross Unrealized Losses	(15,429)	(5,894)
Available-for-Sale Securities, Fair value	801,859	720,128
State And Municipals [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	5,060	6,970
Held-to-Maturity Securities, Gross Unrealized Gains	55	78
Held-to-Maturity Securities, Fair Value	5,115	7,048
Available-for-Sale Securities, Amortized Cost	461,047	453,158
Available-for-Sale Securities, Gross Unrealized Gains	4,833	10,051
Available-for-Sale Securities, Gross Unrealized Losses	(5,444)	(1,886)
Available-for-Sale Securities, Fair value	460,436	461,323
Pass-Through Mortgage Securities [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	295	311
Held-to-Maturity Securities, Gross Unrealized Gains	17	21
Held-to-Maturity Securities, Fair Value	312	332
Available-for-Sale Securities, Amortized Cost	74,603	72,539
Available-for-Sale Securities, Gross Unrealized Gains	24	84
Available-for-Sale Securities, Gross Unrealized Losses	(2,767)	(1,232)
Available-for-Sale Securities, Fair value	71,860	71,391
Collateralized Mortgage Obligations [Member]
Schedule Of Amortized Cost And Estimated Fair Values [Line Items]
Held-to-Maturity Securities, Amortized Cost	220	355
Held-to-Maturity Securities, Gross Unrealized Gains	6	14
Held-to-Maturity Securities, Fair Value	226	369
Available-for-Sale Securities, Amortized Cost	276,781	190,175
Available-for-Sale Securities, Gross Unrealized Gains		15
Available-for-Sale Securities, Gross Unrealized Losses	(7,218)	(2,776)
Available-for-Sale Securities, Fair value	$ 269,563	$ 187,414

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
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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 after other than temporary impairment (OTTI) accretion, of investments in debt securities classified as held-to-maturity.

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Amount of accumulated unrealized gain on investments in debt securities classified as held-to-maturity.

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Fair value of investments in debt securities classified as held-to-maturity.

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