Securities - (Details 1) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Amortized cost and fair value of securities available for sale
Amortized Cost	$ 740,236	$ 686,405
Gross Unrealized Gains	5,998	3,908
Gross Unrealized Losses	(9,228)	(16,065)
Securities available for sale	737,006	674,248
Trust preferred securities
Amortized cost and fair value of securities available for sale
Amortized Cost	21,793	23,749
Gross Unrealized Gains	0	0
Gross Unrealized Losses	(4,801)	(5,360)
Securities available for sale	16,992	18,389
Other debt securities
Amortized cost and fair value of securities available for sale
Amortized Cost	22,519	22,053
Gross Unrealized Gains	427	310
Gross Unrealized Losses	(45)	(218)
Securities available for sale	22,901	22,145
Other equity securities
Amortized cost and fair value of securities available for sale
Amortized Cost			$ 2,842
Obligations of other U.S. Government agencies and corporations
Amortized cost and fair value of securities available for sale
Amortized Cost	2,053	2,066
Gross Unrealized Gains	81	92
Gross Unrealized Losses	0	0
Securities available for sale	2,134	2,158
Government agency mortgage backed securities \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	419,848	414,019
Gross Unrealized Gains	3,317	1,941
Gross Unrealized Losses	(2,288)	(6,643)
Securities available for sale	420,877	409,317
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	50,167	50,628
Gross Unrealized Gains	1,032	696
Gross Unrealized Losses	(146)	(461)
Securities available for sale	51,053	50,863
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	222,110	171,362
Gross Unrealized Gains	1,133	831
Gross Unrealized Losses	(1,948)	(3,367)
Securities available for sale	221,295	168,826
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Amortized cost and fair value of securities available for sale
Amortized Cost	1,746	2,528
Gross Unrealized Gains	8	38
Gross Unrealized Losses	0	(16)
Securities available for sale	$ 1,754	$ 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=75030427&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
-Publisher FASB
-Name Accounting Standards Codification
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