Securities (Details 2) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	$ 227,073	$ 147,039
Unrealized Losses, Less Than 12 Months	(7,509)	(865)
Fair Value, 12 Months or Longer	53	97
Unrealized Losses, 12 Months or Longer	(5)	(5)
Fair Value, Total	227,126	147,136
Unrealized Losses, Total	(7,514)	(870)
U.S. Treasury and U.S. government sponsored entities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	26,363	5,490
Unrealized Losses, Less Than 12 Months	(379)	(1)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	26,363	5,490
Unrealized Losses, Total	(379)	(1)
State and political subdivisions
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	30,253	12,079
Unrealized Losses, Less Than 12 Months	(2,158)	(245)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	30,253	12,079
Unrealized Losses, Total	(2,158)	(245)
Corporate bonds
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	1,521	887
Unrealized Losses, Less Than 12 Months	(21)	(7)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	1,521	887
Unrealized Losses, Total	(21)	(7)
Mortgage-backed securities - residential
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	120,954	97,598
Unrealized Losses, Less Than 12 Months	(3,069)	(476)
Fair Value, 12 Months or Longer	37	52
Unrealized Losses, 12 Months or Longer	(1)	0
Fair Value, Total	120,991	97,650
Unrealized Losses, Total	(3,070)	(476)
Collateralized mortgage obligations
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	22,681	23,132
Unrealized Losses, Less Than 12 Months	(889)	(74)
Fair Value, 12 Months or Longer	0	0
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	22,681	23,132
Unrealized Losses, Total	(889)	(74)
Small business administration
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	25,301	7,853
Unrealized Losses, Less Than 12 Months	(993)	(62)
Fair Value, 12 Months or Longer	8	37
Unrealized Losses, 12 Months or Longer	0	0
Fair Value, Total	25,309	7,890
Unrealized Losses, Total	(993)	(62)
Equity securities
Investment securities with unrealized losses
Fair Value, Less Than 12 Months	0	0
Unrealized Losses, Less Than 12 Months	0	0
Fair Value, 12 Months or Longer	8	8
Unrealized Losses, 12 Months or Longer	(4)	(5)
Fair Value, Total	8	8
Unrealized Losses, Total	$ (4)	$ (5)