Securities - (Details 4) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2016 USD ($) security	Dec. 31, 2015 USD ($) security
Held to Maturity:
Number of positions (securities) | security	26	31
Fair Value, Less than 12 Months	$ 49,436	$ 36,382
Fair Value, 12 Months or More	25,567	43,609
Fair Value, Total	75,003	79,991
Unrealized Losses, Less than 12 months	(281)	(467)
Unrealized Losses, 12 Months or More	(243)	(842)
Unrealized Losses, Total	$ (524)	$ (1,309)
Available for Sale:
Number of positions (securities) | security	53	101
Fair Value, Less than 12 Months	$ 80,510	$ 206,395
Fair Value, 12 Months or More	80,125	103,154
Fair Value, Total	160,635	309,549
Unrealized losses, Less than 12 months	(307)	(1,411)
Unrealized Losses, 12 months or More	(7,179)	(8,134)
Unrealized Losses, Total	$ (7,486)	$ (9,545)
Trust preferred securities
Available for Sale:
Number of positions (securities) | security	3	3
Fair Value, Less than 12 Months	$ 0	$ 0
Fair Value, 12 Months or More	18,946	19,469
Fair Value, Total	18,946	19,469
Unrealized losses, Less than 12 months	0	0
Unrealized Losses, 12 months or More	(5,785)	(5,301)
Unrealized Losses, Total	$ (5,785)	$ (5,301)
Other debt securities
Available for Sale:
Number of positions (securities) | security	3	3
Fair Value, Less than 12 Months	$ 3,637	$ 1,316
Fair Value, 12 Months or More	1,398	3,866
Fair Value, Total	5,035	5,182
Unrealized losses, Less than 12 months	(13)	(3)
Unrealized Losses, 12 months or More	(9)	(31)
Unrealized Losses, Total	$ (22)	$ (34)
Other equity securities
Available for Sale:
Number of positions (securities) | security		0
Fair Value, Less than 12 Months		$ 0
Fair Value, 12 Months or More		0
Fair Value, Total		0
Unrealized losses, Less than 12 months		0
Unrealized Losses, 12 months or More		0
Unrealized Losses, Total		$ 0
Obligations of other U.S. Government agencies and corporations
Held to Maturity:
Number of positions (securities) | security	15	18
Fair Value, Less than 12 Months	$ 40,832	$ 31,567
Fair Value, 12 Months or More	24,745	38,688
Fair Value, Total	65,577	70,255
Unrealized Losses, Less than 12 months	(264)	(414)
Unrealized Losses, 12 Months or More	(241)	(800)
Unrealized Losses, Total	$ (505)	$ (1,214)
Available for Sale:
Number of positions (securities) | security	1	1
Fair Value, Less than 12 Months	$ 3,990	$ 3,981
Fair Value, 12 Months or More	0	0
Fair Value, Total	3,990	3,981
Unrealized losses, Less than 12 months	(10)	(19)
Unrealized Losses, 12 months or More	0	0
Unrealized Losses, Total	$ (10)	$ (19)
Obligations of states and political subdivisions
Held to Maturity:
Number of positions (securities) | security	11	13
Fair Value, Less than 12 Months	$ 8,604	$ 4,815
Fair Value, 12 Months or More	822	4,921
Fair Value, Total	9,426	9,736
Unrealized Losses, Less than 12 months	(17)	(53)
Unrealized Losses, 12 Months or More	(2)	(42)
Unrealized Losses, Total	$ (19)	$ (95)
Government agency mortgage backed securities | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	17	43
Fair Value, Less than 12 Months	$ 31,374	$ 130,306
Fair Value, 12 Months or More	19,176	27,431
Fair Value, Total	50,550	157,737
Unrealized losses, Less than 12 months	(136)	(937)
Unrealized Losses, 12 months or More	(437)	(841)
Unrealized Losses, Total	$ (573)	$ (1,778)
Government agency mortgage backed securities | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	5	9
Fair Value, Less than 12 Months	$ 6,874	$ 16,782
Fair Value, 12 Months or More	808	814
Fair Value, Total	7,682	17,596
Unrealized losses, Less than 12 months	(33)	(104)
Unrealized Losses, 12 months or More	(2)	(3)
Unrealized Losses, Total	$ (35)	$ (107)
Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	24	41
Fair Value, Less than 12 Months	$ 34,635	$ 52,128
Fair Value, 12 Months or More	39,797	51,574
Fair Value, Total	74,432	103,702
Unrealized losses, Less than 12 months	(115)	(347)
Unrealized Losses, 12 months or More	(946)	(1,958)
Unrealized Losses, Total	$ (1,061)	$ (2,305)
Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	0	1
Fair Value, Less than 12 Months	$ 0	$ 1,882
Fair Value, 12 Months or More	0	0
Fair Value, Total	0	1,882
Unrealized losses, Less than 12 months	0	(1)
Unrealized Losses, 12 months or More	0	0
Unrealized Losses, Total	$ 0	$ (1)
Less than 12 Months
Held to Maturity:
Number of positions (securities) | security	19	16
Available for Sale:
Number of positions (securities) | security	28	70
Less than 12 Months | Trust preferred securities
Available for Sale:
Number of positions (securities) | security	0	0
Less than 12 Months | Other debt securities
Available for Sale:
Number of positions (securities) | security	2	1
Less than 12 Months | Other equity securities
Available for Sale:
Number of positions (securities) | security		0
Less than 12 Months | Obligations of other U.S. Government agencies and corporations
Held to Maturity:
Number of positions (securities) | security	10	10
Available for Sale:
Number of positions (securities) | security	1	1
Less than 12 Months | Obligations of states and political subdivisions
Held to Maturity:
Number of positions (securities) | security	9	6
Less than 12 Months | Government agency mortgage backed securities | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	10	34
Less than 12 Months | Government agency mortgage backed securities | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	4	8
Less than 12 Months | Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	11	25
Less than 12 Months | Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	0	1
12 Months or More
Held to Maturity:
Number of positions (securities) | security	7	15
Available for Sale:
Number of positions (securities) | security	25	31
12 Months or More | Trust preferred securities
Available for Sale:
Number of positions (securities) | security	3	3
12 Months or More | Other debt securities
Available for Sale:
Number of positions (securities) | security	1	2
12 Months or More | Other equity securities
Available for Sale:
Number of positions (securities) | security		0
12 Months or More | Obligations of other U.S. Government agencies and corporations
Held to Maturity:
Number of positions (securities) | security	5	8
Available for Sale:
Number of positions (securities) | security	0	0
12 Months or More | Obligations of states and political subdivisions
Held to Maturity:
Number of positions (securities) | security	2	7
12 Months or More | Government agency mortgage backed securities | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	7	9
12 Months or More | Government agency mortgage backed securities | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	1	1
12 Months or More | Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	13	16
12 Months or More | Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Available for Sale:
Number of positions (securities) | security	0	0