Securities (Details 2) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Debt Maturities, Next Twelve Months, Amortized Cost Basis	$ 5,085
Less Than 12 Months
Fair Value	351,666	$ 464,602
Unrealized Losses	(6,102)	(11,155)
More Than 12 Months
Fair Value	82,008	80,151
Unrealized Losses	(2,963)	(3,259)
Total
Fair Value	433,674	544,753
Unrealized Losses	(9,065)	(14,414)
US Government Agencies Debt Securities [Member]
Less Than 12 Months
Fair Value	3,713	12,224
Unrealized Losses	(170)	(377)
More Than 12 Months
Fair Value	0	0
Unrealized Losses	0	0
Total
Fair Value	3,713	12,224
Unrealized Losses	(170)	(377)
Mortgage Backed Securities - Residential
Less Than 12 Months
Fair Value	132,684	202,248
Unrealized Losses	(1,998)	(4,072)
More Than 12 Months
Fair Value	151	152
Unrealized Losses	(1)	(1)
Total
Fair Value	132,835	202,400
Unrealized Losses	(1,999)	(4,073)
Collateralized Mortgage Obligations
Less Than 12 Months
Fair Value	161,147	169,717
Unrealized Losses	(2,372)	(3,086)
More Than 12 Months
Fair Value	81,569	79,999
Unrealized Losses	(2,962)	(3,258)
Total
Fair Value	242,716	249,716
Unrealized Losses	(5,334)	(6,344)
State and Municipal Obligations
Less Than 12 Months
Fair Value	54,121	72,852
Unrealized Losses	(1,562)	(2,396)
More Than 12 Months
Fair Value	288	0
Unrealized Losses	0	0
Total
Fair Value	54,409	72,852
Unrealized Losses	$ (1,562)	(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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