Loans (Details 7) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Credit risk profile by internally assigned grade
Loans	$ 1,721,350	$ 1,584,594	$ 1,544,845
Pass
Credit risk profile by internally assigned grade
Loans	1,644,646	1,479,270
Special mention
Credit risk profile by internally assigned grade
Loans	38,076	44,698
Substandard
Credit risk profile by internally assigned grade
Loans	15,684	31,933
Substandard non-performing
Credit risk profile by internally assigned grade
Loans	22,944	28,693
Commercial and industrial
Credit risk profile by internally assigned grade
Loans	510,739	426,930	393,729
Commercial and industrial | Pass
Credit risk profile by internally assigned grade
Loans	486,140	404,045
Commercial and industrial | Special mention
Credit risk profile by internally assigned grade
Loans	12,983	11,097
Commercial and industrial | Substandard
Credit risk profile by internally assigned grade
Loans	3,616	4,482
Commercial and industrial | Substandard non-performing
Credit risk profile by internally assigned grade
Loans	8,000	7,306
Construction and development excluding undeveloped land
Credit risk profile by internally assigned grade
Loans	91,719	85,456	147,637
Construction and development excluding undeveloped land | Pass
Credit risk profile by internally assigned grade
Loans	79,896	78,621
Construction and development excluding undeveloped land | Special mention
Credit risk profile by internally assigned grade
Loans	7,091	6,284
Construction and development excluding undeveloped land | Substandard
Credit risk profile by internally assigned grade
Loans	4,706
Construction and development excluding undeveloped land | Substandard non-performing
Credit risk profile by internally assigned grade
Loans	26	551
Undeveloped land
Credit risk profile by internally assigned grade
Loans	37,871	45,797
Undeveloped land | Pass
Credit risk profile by internally assigned grade
Loans	30,366	34,388
Undeveloped land | Special mention
Credit risk profile by internally assigned grade
Loans		547
Undeveloped land | Substandard
Credit risk profile by internally assigned grade
Loans	165	550
Undeveloped land | Substandard non-performing
Credit risk profile by internally assigned grade
Loans	7,340	10,312
Real estate mortgage
Credit risk profile by internally assigned grade
Loans	1,046,823	989,631	966,665
Real estate mortgage | Pass
Credit risk profile by internally assigned grade
Loans	1,014,216	925,674
Real estate mortgage | Special mention
Credit risk profile by internally assigned grade
Loans	17,916	26,770
Real estate mortgage | Substandard
Credit risk profile by internally assigned grade
Loans	7,197	26,901
Real estate mortgage | Substandard non-performing
Credit risk profile by internally assigned grade
Loans	7,494	10,286
Consumer
Credit risk profile by internally assigned grade
Loans	34,198	36,780	36,814
Consumer | Pass
Credit risk profile by internally assigned grade
Loans	34,028	36,542
Consumer | Special mention
Credit risk profile by internally assigned grade
Loans	86
Consumer | Substandard non-performing
Credit risk profile by internally assigned grade
Loans	$ 84	$ 238