Securities (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 security	Dec. 31, 2013 security
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	47	141
Fair Value, Held to Maturity, Less than 12 Months	$ 4,353	$ 165,250
Fair Value, Held to Maturity, 12 Months or More	129,226	10,023
Fair Value, Held to Maturity, Total	133,579	175,273
Unrealized Losses, Held to Maturity, Less than 12 months	(30)	(10,404)
Unrealized Losses, Held to Maturity, 12 Months or More	(3,083)	(1,006)
Unrealized Losses, Held to Maturity, Total	(3,113)	(11,410)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	49	68
Fair Value, Available for Sale, Less than 12 Months	51,093	230,823
Fair Value, Available for Sale, 12 Months or More	152,374	48,342
Fair Value, Available for Sale, Total	203,467	279,165
Unrealized Losses, Available for Sale, Less than 12 months	(177)	(7,921)
Unrealized Losses, Available for Sale, 12 months or More	(10,289)	(12,120)
Unrealized Losses, Available for Sale, Total	(10,466)	(20,041)
Trust preferred securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	3	3
Fair Value, Available for Sale, Less than 12 Months	0	0
Fair Value, Available for Sale, 12 Months or More	18,503	16,456
Fair Value, Available for Sale, Total	18,503	16,456
Unrealized Losses, Available for Sale, Less than 12 months	0	0
Unrealized Losses, Available for Sale, 12 months or More	(6,781)	(9,933)
Unrealized Losses, Available for Sale, Total	(6,781)	(9,933)
Other debt securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	2	4
Fair Value, Available for Sale, Less than 12 Months	0	7,100
Fair Value, Available for Sale, 12 Months or More	4,175	1,897
Fair Value, Available for Sale, Total	4,175	8,997
Unrealized Losses, Available for Sale, Less than 12 months	0	(217)
Unrealized Losses, Available for Sale, 12 months or More	(74)	(13)
Unrealized Losses, Available for Sale, Total	(74)	(230)
Other equity securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
Fair Value, Available for Sale, Less than 12 Months	0	0
Fair Value, Available for Sale, 12 Months or More	0	0
Fair Value, Available for Sale, Total	0	0
Unrealized Losses, Available for Sale, Less than 12 months	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Unrealized Losses, Available for Sale, Total	0	0
Obligations of other U.S. Government agencies and corporations
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	28	28
Fair Value, Held to Maturity, Less than 12 Months	1,000	105,747
Fair Value, Held to Maturity, 12 Months or More	119,174	9,090
Fair Value, Held to Maturity, Total	120,174	114,837
Unrealized Losses, Held to Maturity, Less than 12 months	(1)	(7,826)
Unrealized Losses, Held to Maturity, 12 Months or More	(2,914)	(901)
Unrealized Losses, Held to Maturity, Total	(2,915)	(8,727)
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	1	1
Fair Value, Available for Sale, Less than 12 Months	0	3,799
Fair Value, Available for Sale, 12 Months or More	3,881	0
Fair Value, Available for Sale, Total	3,881	3,799
Unrealized Losses, Available for Sale, Less than 12 months	0	(201)
Unrealized Losses, Available for Sale, 12 months or More	(119)	0
Unrealized Losses, Available for Sale, Total	(119)	(201)
Obligations of states and political subdivisions
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	19	113
Fair Value, Held to Maturity, Less than 12 Months	3,353	59,503
Fair Value, Held to Maturity, 12 Months or More	10,052	933
Fair Value, Held to Maturity, Total	13,405	60,436
Unrealized Losses, Held to Maturity, Less than 12 months	(29)	(2,578)
Unrealized Losses, Held to Maturity, 12 Months or More	(169)	(105)
Unrealized Losses, Held to Maturity, Total	(198)	(2,683)
Government agency mortgage backed securities \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	16	35
Fair Value, Available for Sale, Less than 12 Months	18,924	134,858
Fair Value, Available for Sale, 12 Months or More	49,612	13,239
Fair Value, Available for Sale, Total	68,536	148,097
Unrealized Losses, Available for Sale, Less than 12 months	(39)	(3,451)
Unrealized Losses, Available for Sale, 12 months or More	(793)	(963)
Unrealized Losses, Available for Sale, Total	(832)	(4,414)
Government agency mortgage backed securities \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	3	4
Fair Value, Available for Sale, Less than 12 Months	0	16,570
Fair Value, Available for Sale, 12 Months or More	10,651	0
Fair Value, Available for Sale, Total	10,651	16,570
Unrealized Losses, Available for Sale, Less than 12 months	0	(584)
Unrealized Losses, Available for Sale, 12 months or More	(137)	0
Unrealized Losses, Available for Sale, Total	(137)	(584)
Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	24	21
Fair Value, Available for Sale, Less than 12 Months	32,169	68,496
Fair Value, Available for Sale, 12 Months or More	65,552	16,750
Fair Value, Available for Sale, Total	97,721	85,246
Unrealized Losses, Available for Sale, Less than 12 months	(138)	(3,468)
Unrealized Losses, Available for Sale, 12 months or More	(2,385)	(1,211)
Unrealized Losses, Available for Sale, Total	(2,523)	(4,679)
Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
Fair Value, Available for Sale, Less than 12 Months	0	0
Fair Value, Available for Sale, 12 Months or More	0	0
Fair Value, Available for Sale, Total	0	0
Unrealized Losses, Available for Sale, Less than 12 months	0	0
Unrealized Losses, Available for Sale, 12 months or More	0	0
Unrealized Losses, Available for Sale, Total	$ 0	$ 0
Less than 12 Months
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	5	137
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	9	57
Less than 12 Months \| Trust preferred securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
Less than 12 Months \| Other debt securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	3
Less than 12 Months \| Other equity securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
Less than 12 Months \| Obligations of other U.S. Government agencies and corporations
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	2	26
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	1
Less than 12 Months \| Obligations of states and political subdivisions
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	3	111
Less than 12 Months \| Government agency mortgage backed securities \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	3	32
Less than 12 Months \| Government agency mortgage backed securities \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	4
Less than 12 Months \| Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	6	17
Less than 12 Months \| Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
12 Months or More
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	42	4
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	40	11
12 Months or More \| Trust preferred securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	3	3
12 Months or More \| Other debt securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	2	1
12 Months or More \| Other equity securities
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0
12 Months or More \| Obligations of other U.S. Government agencies and corporations
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	26	2
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	1	0
12 Months or More \| Obligations of states and political subdivisions
Held-to-maturity Securities, Continuous Unrealized Loss Position [Abstract]
Held-to-maturity, securities in unrealized loss positions (securities)	16	2
12 Months or More \| Government agency mortgage backed securities \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	13	3
12 Months or More \| Government agency mortgage backed securities \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	3	0
12 Months or More \| Government agency collateralized mortgage obligations \| Residential mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	18	4
12 Months or More \| Government agency collateralized mortgage obligations \| Commercial mortgage backed securities:
Available-for-sale Securities, Continuous Unrealized Loss Position [Abstract]
Available-for-sale, securities in unrealized loss positions (securities)	0	0

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

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