Investments (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($) Security	Mar. 31, 2015 USD ($)	Dec. 31, 2015 USD ($)
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	$ 366,920		$ 356,399
Gross Unrealized Gains	5,237		4,139
Gross Unrealized Losses	(232)		(801)
Fair Value	$ 371,925		359,737
Number of securities owned with fair value less than cost | Security	44
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	$ 57,705		156,454
Twelve Months or Greater, Fair Value	5,266		5,279
Total, Fair Value	62,971		161,733
Less than Twelve Months, Gross Unrealized Losses	(191)		(748)
Twelve Months or Greater, Gross Unrealized Losses	(41)		(53)
Total, Gross Unrealized Losses	$ (232)		(801)
Duration securities impaired, Minimum	1 year
Proceeds from sale of securities available-for-sale	$ 5,020	$ 14,623
Realized investment gains (losses) [Abstract]
Gross gains	27	137
Gross losses	0	(11)
Net gains	27	$ 126
Investment securities pledged as collateral	221,900		203,800
Amortized Cost [Abstract]
Due in one year or less	37,238
Due after one year through five years	198,445
Due after five years through ten years	43,004
Due after ten years	86,232
Total	364,919
Fair Value [Abstract]
Due in one year or less	37,445
Due after one year through five years	200,491
Due after five years through ten years	43,960
Due after ten years	87,688
Total	369,584
U.S. Agency Securities [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	212,978		199,749
Gross Unrealized Gains	1,377		369
Gross Unrealized Losses	(36)		(527)
Fair Value	214,319		199,591
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	34,231		123,591
Twelve Months or Greater, Fair Value	0		0
Total, Fair Value	34,231		123,591
Less than Twelve Months, Gross Unrealized Losses	(36)		(527)
Twelve Months or Greater, Gross Unrealized Losses	0		0
Total, Gross Unrealized Losses	(36)		(527)
US Treasury Securities [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	5,078		10,103
Gross Unrealized Gains	4		0
Gross Unrealized Losses	0		(21)
Fair Value	5,082		10,082
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value			10,082
Twelve Months or Greater, Fair Value			0
Total, Fair Value			10,082
Less than Twelve Months, Gross Unrealized Losses			(21)
Twelve Months or Greater, Gross Unrealized Losses			0
Total, Gross Unrealized Losses			(21)
Obligations of State and Political Subdivisions [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	101,685		99,856
Gross Unrealized Gains	3,089		3,080
Gross Unrealized Losses	(116)		(73)
Fair Value	104,658		102,863
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	12,058		7,023
Twelve Months or Greater, Fair Value	2,197		2,914
Total, Fair Value	14,255		9,937
Less than Twelve Months, Gross Unrealized Losses	(96)		(57)
Twelve Months or Greater, Gross Unrealized Losses	(20)		(16)
Total, Gross Unrealized Losses	(116)		(73)
Corporate Obligations [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	12,503		14,583
Gross Unrealized Gains	52		68
Gross Unrealized Losses	(19)		(86)
Fair Value	12,536		14,565
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	4,257		5,822
Twelve Months or Greater, Fair Value	2,140		2,138
Total, Fair Value	6,397		7,960
Less than Twelve Months, Gross Unrealized Losses	(14)		(61)
Twelve Months or Greater, Gross Unrealized Losses	(5)		(25)
Total, Gross Unrealized Losses	(19)		(86)
Mortgage-backed Securities in Government Sponsored Entities [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	32,675		30,107
Gross Unrealized Gains	351		186
Gross Unrealized Losses	(37)		(89)
Fair Value	32,989		30,204
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	6,174		9,830
Twelve Months or Greater, Fair Value	929		227
Total, Fair Value	7,103		10,057
Less than Twelve Months, Gross Unrealized Losses	(21)		(77)
Twelve Months or Greater, Gross Unrealized Losses	(16)		(12)
Total, Gross Unrealized Losses	(37)		(89)
Equity Securities in Financial Institutions [Member]
Available for Sale Securities Amortized Cost, Gross Unrealized Gains and Losses, and Fair Value [Abstract]
Amortized Cost	2,001		2,001
Gross Unrealized Gains	364		436
Gross Unrealized Losses	(24)		(5)
Fair Value	2,341		2,432
Available-For-Sale Securities, Fair Value and Gross Unrealized Losses [Abstract]
Less than Twelve Months, Fair Value	985		106
Twelve Months or Greater, Fair Value	0		0
Total, Fair Value	985		106
Less than Twelve Months, Gross Unrealized Losses	(24)		(5)
Twelve Months or Greater, Gross Unrealized Losses	0		0
Total, Gross Unrealized Losses	$ (24)		$ (5)