Loans (Details 2) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	$ 1,728,619	$ 1,721,350
Loans individually evaluated for impairment	20,022	22,507
Loans collectively evaluated for impairment	1,706,389	1,696,413
Loans acquired with deteriorated credit quality	2,208	2,430
Allowance for loan losses
Balance at the beginning of the period	28,522	31,881
Provision	350	6,550
Charge-offs	(519)	(11,964)
Recoveries	238	2,055
Balance at the end of the period	28,591	28,522
Allowance for loans individually evaluated for impairment	1,267	1,452
Allowance for loans collectively evaluated for impairment	27,324	27,070
Commercial and industrial
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	511,247	510,739
Loans individually evaluated for impairment	7,653	7,579
Loans collectively evaluated for impairment	502,967	502,535
Loans acquired with deteriorated credit quality	627	625
Allowance for loan losses
Balance at the beginning of the period	7,644	5,949
Provision	(145)	1,583
Charge-offs		(457)
Recoveries	9	569
Balance at the end of the period	7,508	7,644
Allowance for loans individually evaluated for impairment	746	762
Allowance for loans collectively evaluated for impairment	6,762	6,882
Construction and development excluding undeveloped land
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	88,108	99,719
Loans individually evaluated for impairment	26	26
Loans collectively evaluated for impairment	87,021	98,428
Loans acquired with deteriorated credit quality	1,061	1,265
Allowance for loan losses
Balance at the beginning of the period	2,555	4,536
Provision	(628)	(2,119)
Charge-offs		(25)
Recoveries		163
Balance at the end of the period	1,927	2,555
Allowance for loans collectively evaluated for impairment	1,927	2,555
Undeveloped land
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	29,209	29,871
Loans individually evaluated for impairment	6,988	7,340
Loans collectively evaluated for impairment	22,221	22,531
Allowance for loan losses
Balance at the beginning of the period	5,376
Provision	925	13,256
Charge-offs	(30)	(7,961)
Recoveries	31	81
Balance at the end of the period	6,302	5,376
Allowance for loans collectively evaluated for impairment	6,302	5,376
Real estate mortgage
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	1,066,595	1,046,823
Loans individually evaluated for impairment	5,273	7,478
Loans collectively evaluated for impairment	1,060,820	1,038,824
Loans acquired with deteriorated credit quality	502	521
Allowance for loan losses
Balance at the beginning of the period	12,604	14,288
Provision	185	490
Charge-offs	(294)	(2,758)
Recoveries	20	584
Balance at the end of the period	12,515	12,604
Allowance for loans individually evaluated for impairment	439	606
Allowance for loans collectively evaluated for impairment	12,076	11,998
Consumer
Balance in the recorded investment in loans and allowance for loan losses by portfolio segment and based on impairment method
Loans	33,460	34,198
Loans individually evaluated for impairment	82	84
Loans collectively evaluated for impairment	33,360	34,095
Loans acquired with deteriorated credit quality	18	19
Allowance for loan losses
Balance at the beginning of the period	343	362
Provision	13	86
Charge-offs	(195)	(763)
Recoveries	178	658
Balance at the end of the period	339	343
Allowance for loans individually evaluated for impairment	82	84
Allowance for loans collectively evaluated for impairment	257	259
Unallocated
Allowance for loan losses
Balance at the beginning of the period		6,746
Provision		$ (6,746)