Investment Securities (Details 2) (USD $)	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Fair Value
Less than 12 Months	$ 322,772,000	$ 296,803,000
12 months or Longer	30,776,000	21,860,000
Total	353,548,000	318,663,000
Unrealized Losses
Less than 12 Months	(5,885,000)	(8,321,000)
12 months or Longer	(1,005,000)	(622,000)
Total	(6,890,000)	(8,943,000)
Investment securities pledged as collateral	248,110,000	237,420,000
U.S. Treasury and Federal agencies securities
Fair Value
Less than 12 Months	210,143,000	153,868,000
12 months or Longer	15,044,000	15,085,000
Total	225,187,000	168,953,000
Unrealized Losses
Less than 12 Months	(3,876,000)	(4,404,000)
12 months or Longer	(147,000)	(123,000)
Total	(4,023,000)	(4,527,000)
U.S. States and political subdivisions securities
Fair Value
Less than 12 Months	34,278,000	37,115,000
12 months or Longer	915,000	1,419,000
Total	35,193,000	38,534,000
Unrealized Losses
Less than 12 Months	(528,000)	(814,000)
12 months or Longer	(27,000)	(33,000)
Total	(555,000)	(847,000)
Mortgage-backed securities - Federal agencies
Fair Value
Less than 12 Months	72,185,000	99,488,000
12 months or Longer	14,813,000	5,352,000
Total	86,998,000	104,840,000
Unrealized Losses
Less than 12 Months	(1,438,000)	(3,099,000)
12 months or Longer	(829,000)	(464,000)
Total	(2,267,000)	(3,563,000)
Corporate debt securities
Fair Value
Less than 12 Months	6,066,000	6,332,000
12 months or Longer	0	0
Total	6,066,000	6,332,000
Unrealized Losses
Less than 12 Months	(43,000)	(4,000)
12 months or Longer	0	0
Total	(43,000)	(4,000)
Foreign government and other securities
Fair Value
Less than 12 Months	100,000	0
12 months or Longer	0	0
Total	100,000	0
Unrealized Losses
Less than 12 Months	0	0
12 months or Longer	0	0
Total	0	0
Total debt securities
Fair Value
Less than 12 Months	322,772,000	296,803,000
12 months or Longer	30,772,000	21,856,000
Total	353,544,000	318,659,000
Unrealized Losses
Less than 12 Months	(5,885,000)	(8,321,000)
12 months or Longer	(1,003,000)	(620,000)
Total	(6,888,000)	(8,941,000)
Marketable equity securities
Fair Value
Less than 12 Months	0	0
12 months or Longer	4,000	4,000
Total	4,000	4,000
Unrealized Losses
Less than 12 Months	0	0
12 months or Longer	(2,000)	(2,000)
Total	$ (2,000)	$ (2,000)