Securities (Details 3) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Amortized Cost
Due within one year	$ 11,838
Due after one year through five years	52,018
Due after five years through ten years	229,292
Due after ten years	145,135
Amortized Cost, Held to Maturity	438,283	412,075
Fair Value
Due within one year	11,966
Due after one year through five years	53,704
Due after five years through ten years	228,436
Due after ten years	152,161
Fair Value	446,267	408,576
Amortized Cost
Due within one year	0
Due after one year through five years	1,071
Due after five years through ten years	5,061
Due after ten years	27,371
Amortized Cost	574,917	513,594
Amortized Cost	574,917
Fair Value
Due within one year	0
Due after one year through five years	1,149
Due after five years through ten years	4,973
Due after ten years	18,309
Securities available for sale	569,048	501,254
Other debt securities
Amortized Cost
Amortized Cost	18,482	19,544
Fair Value
Securities available for sale	18,701	19,554
Other equity securities
Amortized Cost
Amortized Cost	3,054	2,775
Other equity securities	3,054
Fair Value
Securities available for sale	4,458	4,317
Government agency mortgage backed securities | Residential mortgage backed securities:
Amortized Cost
Amortized Cost	303,203	261,659
Fair Value
Securities available for sale	305,668	259,992
Government agency mortgage backed securities | Commercial mortgage backed securities:
Amortized Cost
Amortized Cost	46,154	41,252
Fair Value
Securities available for sale	47,383	42,041
Government agency collateralized mortgage obligations | Residential mortgage backed securities:
Amortized Cost
Amortized Cost	165,265	149,682
Fair Value
Securities available for sale	162,946	146,545
Government agency collateralized mortgage obligations | Commercial mortgage backed securities:
Amortized Cost
Amortized Cost	5,256	5,007
Fair Value
Securities available for sale	$ 5,461	$ 5,066