Securities Amortized costs and fair values of securities available for sale (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 371,733	$ 342,233
Gross Unrealized Gains	5,798	8,068
Gross Unrealized Losses	(2,960)	(2,038)
Fair Value	374,571	348,263
U.S. government agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	79,005	41,317
Gross Unrealized Gains	315	283
Gross Unrealized Losses	(380)	(203)
Fair Value	78,940	41,397
Obligations of states and political subdivisions [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	74,071	55,541
Gross Unrealized Gains	1,956	2,408
Gross Unrealized Losses	(434)	(209)
Fair Value	75,593	57,740
Mortgage-backed securities, Agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	129,360	169,257
Gross Unrealized Gains	3,046	4,698
Gross Unrealized Losses	(745)	(742)
Fair Value	131,661	173,213
Mortgage-backed securities, Non-agency [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	12,782	28,235
Gross Unrealized Gains	33	115
Gross Unrealized Losses	(38)	(227)
Fair Value	12,777	28,123
Other Asset Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	58,958	31,338
Gross Unrealized Gains	426	433
Gross Unrealized Losses	(603)	(58)
Fair Value	58,781	31,713
Corporate preferred stock [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		0
Gross Unrealized Gains		0
Gross Unrealized Losses		0
Fair Value		0
Corporate Debt Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	17,557	16,545
Gross Unrealized Gains	22	131
Gross Unrealized Losses	(760)	(599)
Fair Value	$ 16,819	$ 16,077