Securities (Details 2) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	$ 5,342
Less Than 12 Months
Fair Value	216,956	$ 464,602
Unrealized Losses	(2,656)	(11,155)
More Than 12 Months
Fair Value	87,785	80,151
Unrealized Losses	(2,544)	(3,259)
Total
Fair Value	304,741	544,753
Unrealized Losses	(5,200)	(14,414)
US Government Agencies Debt Securities [Member]
Less Than 12 Months
Fair Value	13,691	12,224
Unrealized Losses	(186)	(377)
More Than 12 Months
Fair Value	0	0
Unrealized Losses	0	0
Total
Fair Value	13,691	12,224
Unrealized Losses	(186)	(377)
Mortgage Backed Securities - Residential
Less Than 12 Months
Fair Value	60,513	202,248
Unrealized Losses	(806)	(4,072)
More Than 12 Months
Fair Value	3,698	152
Unrealized Losses	(55)	(1)
Total
Fair Value	64,211	202,400
Unrealized Losses	(861)	(4,073)
Mortgage Backed Securities - Commercial
Less Than 12 Months
Fair Value	0
Unrealized Losses	0
More Than 12 Months
Fair Value	0
Unrealized Losses	0
Total
Fair Value	0
Unrealized Losses	0
Collateralized Mortgage Obligations
Less Than 12 Months
Fair Value	128,330	169,717
Unrealized Losses	(1,541)	(3,086)
More Than 12 Months
Fair Value	72,731	79,999
Unrealized Losses	(2,204)	(3,258)
Total
Fair Value	201,061	249,716
Unrealized Losses	(3,745)	(6,344)
State and Municipal Obligations
Less Than 12 Months
Fair Value	14,422	72,852
Unrealized Losses	(123)	(2,396)
More Than 12 Months
Fair Value	11,356	0
Unrealized Losses	(285)	0
Total
Fair Value	25,778	72,852
Unrealized Losses	$ (408)	(2,396)
Collateralized Debt Obligations
Less Than 12 Months
Fair Value		7,561
Unrealized Losses		(1,224)
More Than 12 Months
Fair Value		0
Unrealized Losses		0
Total
Fair Value		7,561
Unrealized Losses		$ (1,224)

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