Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	$ 824,222	$ 855,521
Unrealized Gains	(16,402)	(12,618)
Unrealized Losses	(5,200)	(14,414)
Securities available-for-sale	835,424	853,725
US Government Agencies Debt Securities [Member]
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	14,690	13,594
Unrealized Gains	(30)	(32)
Unrealized Losses	(186)	(377)
Securities available-for-sale	14,534	13,249
Mortgage Backed Securities - Residential
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	225,789	261,878
Unrealized Gains	(3,412)	(3,200)
Unrealized Losses	(861)	(4,073)
Securities available-for-sale	228,340	261,005
Mortgage Backed Securities - Commercial
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	1	4
Unrealized Gains	0	0
Unrealized Losses	0	0
Securities available-for-sale	1	4
Collateralized Mortgage Obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	349,949	353,499
Unrealized Gains	(1,401)	(1,021)
Unrealized Losses	(3,745)	(6,344)
Securities available-for-sale	347,605	348,176
State and Municipal Obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	224,978	217,365
Unrealized Gains	(6,682)	(3,954)
Unrealized Losses	(408)	(2,396)
Securities available-for-sale	231,252	218,923
Collateralized Debt Obligations
Amortized cost and fair value of investments classified as available for sale
Amortized Cost	8,815	9,181
Unrealized Gains	(4,877)	(4,411)
Unrealized Losses	0	(1,224)
Securities available-for-sale	$ 13,692	$ 12,368

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
-SubTopic 10
-Section 50
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=82896770&loc=d3e26610-111562

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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