Securities, Securities in Continuous Unrealized Loss Position (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	$ 270,346	$ 115,100
12 Months or More	107,867	172,906
Total	378,213	288,006
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(1,741)	(663)
12 Months or More	(2,286)	(4,904)
Total	(4,027)	(5,567)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	268,605	114,437
12 Months or More	105,581	168,002
Total	374,186	282,439
Held-to-maturity, amortized cost [Abstract]
12 months or more	480	480
Held-to-maturity, gross unrealized losses [Abstract]
12 months or more	(12)	(19)
Held-to-maturity, fair value [Abstract]
12 months or more	468	461
U.S. Treasury and Government Agencies [Member]
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	142,147	31,185
12 Months or More	54,772	65,209
Total	196,919	96,394
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(487)	(87)
12 Months or More	(864)	(2,053)
Total	(1,351)	(2,140)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	141,660	31,098
12 Months or More	53,908	63,156
Total	195,568	94,254
State and Political Subdivisions [Member]
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	11,190	8,800
12 Months or More	3,187	21,308
Total	14,377	30,108
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(106)	(23)
12 Months or More	(51)	(443)
Total	(157)	(466)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	11,084	8,777
12 Months or More	3,136	20,865
Total	14,220	29,642
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	92,009	50,115
12 Months or More	49,908	86,389
Total	141,917	136,504
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(899)	(442)
12 Months or More	(1,371)	(2,408)
Total	(2,270)	(2,850)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	91,110	49,673
12 Months or More	48,537	83,981
Total	139,647	133,654
Debt Securities [Member]
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	245,346	90,100
12 Months or More	107,867	172,906
Total	353,213	263,006
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(1,492)	(552)
12 Months or More	(2,286)	(4,904)
Total	(3,778)	(5,456)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	243,854	89,548
12 Months or More	105,581	168,002
Total	349,435	257,550
CRA Investments Funds [Member]
Available-for-sale, amortized cost [Abstract]
Less Than 12 Months	25,000	25,000
12 Months or More	0	0
Total	25,000	25,000
Available-for-sale, gross unrealized losses [Abstract]
Less Than 12 Months	(249)	(111)
12 Months or More	0	0
Total	(249)	(111)
Available-for-sale, fair value [Abstract]
Less Than 12 Months	24,751	24,889
12 Months or More	0	0
Total	24,751	24,889
U.S. Treasury and Government Agencies [Member]
Held-to-maturity, amortized cost [Abstract]
12 months or more	480	480
Held-to-maturity, gross unrealized losses [Abstract]
12 months or more	(12)	(19)
Held-to-maturity, fair value [Abstract]
12 months or more	$ 468	$ 461