Securities (Details 6) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2015	Dec. 31, 2014
Proceeds from sales of securities and the resulting gains and losses
Proceeds	$ 58,592	$ 108,603
Gross gains	288	1,008
Gross losses	$ (241)	$ (911)
Available-for-sale, Amortized Cost
Due after 3 months through one year			$ 4,919
Due after one through five years			19,794
Due after five through ten years			38,979
Due after ten years			22,228
Agency mortgage-backed securities			166,943
Total			252,863
Available-for-sale, Estimated Fair Value
Due after 3 months through one year			4,932
Due after one through five years			20,200
Due after five through ten years			39,594
Due after ten years			22,285
Agency mortgage-backed securities			170,399
Estimated Fair Value			257,410	$ 206,335
Held-to-maturity, Amortized Cost
Due after 3 months or less			1,090
Due after 3 months through one year			2,066
Due after one through five years			4,810
Due after five through ten years			13,415
Due after ten years			73,323
Agency mortgage-backed securities			16,300
Total			111,004	95,362
Held-to-maturity, Estimated Fair Value
Due after 3 months or less			1,146
Due after 3 months through one year			2,089
Due after one through five years			4,876
Due after five through ten years			13,911
Due after ten years			71,803
Agency mortgage-backed securities			16,210
Estimated Fair Value			$ 110,035	$ 94,953