Securities - (Details 1) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016	Mar. 31, 2016
Amortized cost and fair value of securities available for sale
Amortized Cost	$ 704,305	$ 686,405
Gross Unrealized Gains	4,810	3,908
Gross Unrealized Losses	(12,230)	(16,065)
Securities available for sale	696,885	674,248
Trust preferred securities
Amortized cost and fair value of securities available for sale
Amortized Cost	22,646	23,749
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(4,823)	(5,360)
Securities available for sale	17,823	18,389
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	22,442	22,053
Gross Unrealized Gains	354	310
Gross Unrealized Losses	(140)	(218)
Securities available for sale	22,656	22,145
Other equity securities
Amortized cost and fair value of securities available for sale
Amortized Cost			$ 75
Obligations of other U.S. Government agencies and corporations
Amortized cost and fair value of securities available for sale
Amortized Cost	2,060	2,066
Gross Unrealized Gains	89	92
Gross Unrealized Losses	0	0
Securities available for sale	2,149	2,158
Government agency mortgage backed securities \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	412,710	414,019
Gross Unrealized Gains	2,710	1,941
Gross Unrealized Losses	(4,165)	(6,643)
Securities available for sale	411,255	409,317
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	50,397	50,628
Gross Unrealized Gains	777	696
Gross Unrealized Losses	(302)	(461)
Securities available for sale	50,872	50,863
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	192,294	171,362
Gross Unrealized Gains	879	831
Gross Unrealized Losses	(2,787)	(3,367)
Securities available for sale	190,386	168,826
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	1,756	2,528
Gross Unrealized Gains	1	38
Gross Unrealized Losses	(13)	(16)
Securities available for sale	$ 1,744	$ 2,550

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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