Securities (Schedule of Securities with Unrealized Losses) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2009 USD ($)	Dec. 31, 2017 USD ($) investment	Dec. 31, 2016 USD ($) investment
Less than 12 Months
Fair Value		$ 205,584	$ 464,958
Unrealized Loss		(2,285)	(12,460)
12 Months or More
Fair Value		274,681	47,271
Unrealized Loss		(7,865)	(1,636)
Total
Fair Value		480,265	512,229
Unrealized Loss		(10,150)	$ (14,096)
Number of equity securities held in non-controlling investment banking \| investment			1
Original investment of equity security	$ 1,350
Obligations of State and Political Subdivisions
Less than 12 Months
Fair Value		33,230	$ 108,918
Unrealized Loss		(237)	(3,678)
12 Months or More
Fair Value		24,161	0
Unrealized Loss		(624)	0
Total
Fair Value		57,391	108,918
Unrealized Loss		(861)	(3,678)
MBS/CMO – Residential
Less than 12 Months
Fair Value		172,354	356,040
Unrealized Loss		(2,048)	(8,782)
12 Months or More
Fair Value		250,520	47,271
Unrealized Loss		(7,241)	(1,636)
Total
Fair Value		422,874	403,311
Unrealized Loss		(9,289)	(10,418)
Equity Securities
Less than 12 Months
Fair Value		0	0
Unrealized Loss		0	0
12 Months or More
Fair Value		0	0
Unrealized Loss		0	0
Total
Fair Value		0	0
Unrealized Loss		$ 0	$ 0
Number of equity securities held in non-controlling investment banking \| investment		1
Other than temporary impairment losses in available for sale securities recognized	$ 997

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Non-controlling Investment in a Single Banking Organization, Number

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Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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-Publisher FASB
-Name Accounting Standards Codification
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