Securities (Schedule of Securities Available-for-Sale) (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 821,194	$ 821,254
Gross Unrealized Gains	11,127	5,436
Gross Unrealized Losses	(7,724)	(14,079)
Fair Value	824,597	812,611
Obligations of State and Political Subdivisions
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	283,892	291,449
Gross Unrealized Gains	8,640	4,407
Gross Unrealized Losses	(215)	(1,323)
Fair Value	292,317	294,533
MBS/CMO - Residential
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	537,302	529,805
Gross Unrealized Gains	2,487	1,029
Gross Unrealized Losses	(7,509)	(12,756)
Fair Value	$ 532,280	$ 518,078

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Section 50
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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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-Publisher FASB
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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-Publisher FASB
-Name Accounting Standards Codification
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