Allowance for Loan Losses (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Dec. 31, 2012
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	$ 28,380	$ 29,483	$ 28,594	$ 30,915
Charge-offs	(794)	(746)	(3,520)	(4,309)
Recoveries	91	63	437	1,684
Provision for / (Reallocation of) loan losses	1,078	807	3,244	1,317
Balance at the end of period	28,755	29,607	28,755	29,607
Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	12,178	10,733	9,912	11,805
Charge-offs	(140)	(323)	(2,318)	(1,223)
Recoveries	19	57	164	1,514
Provision for / (Reallocation of) loan losses	1,387	(6)	5,686	(1,635)
Balance at the end of period	13,444	10,461	13,444	10,461
Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	3,725	3,493	4,021	2,979
Charge-offs	(189)	(40)	(189)	(1,040)
Recoveries	0	0	155	8
Provision for / (Reallocation of) loan losses	345	585	(106)	2,091
Balance at the end of period	3,881	4,038	3,881	4,038
Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	6,287	4,432	5,369	4,394
Charge-offs	0	0	0	(292)
Recoveries	0	0	0	11
Provision for / (Reallocation of) loan losses	(31)	806	887	1,125
Balance at the end of period	6,256	5,238	6,256	5,238
One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	1,098	1,148	1,221	794
Charge-offs	0	(94)	(52)	(212)
Recoveries	0	0	0	0
Provision for / (Reallocation of) loan losses	5	137	(66)	609
Balance at the end of period	1,103	1,191	1,103	1,191
Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	2,207	3,820	3,131	4,823
Charge-offs	(423)	0	(423)	(475)
Recoveries	0	0	0	125
Provision for / (Reallocation of) loan losses	(291)	(374)	(1,215)	(1,027)
Balance at the end of period	1,493	3,446	1,493	3,446
Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	639	3,352	2,309	3,800
Charge-offs	0	0	(142)	(445)
Recoveries	0	0	32	0
Provision for / (Reallocation of) loan losses	(19)	(553)	(1,579)	(556)
Balance at the end of period	620	2,799	620	2,799
Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	1,418	1,577	1,761	1,410
Charge-offs	(42)	(289)	(396)	(622)
Recoveries	72	6	86	26
Provision for / (Reallocation of) loan losses	64	357	61	837
Balance at the end of period	1,512	1,651	1,512	1,651
Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Balance at the beginning of period	828	928	870	910
Charge-offs	0	0	0	0
Recoveries	0	0	0	0
Provision for / (Reallocation of) loan losses	(382)	(145)	(424)	(127)
Balance at the end of period	446	783	446	783
Originated loans [Member]
Schedule of allowance for loan losses on the basis of impairment method
Charge-offs	(706)	(588)	(3,195)	(3,883)
Recoveries	91	63	437	1,684
Individually evaluated for impairment	4,192		4,192		4,359
Collectively evaluated for impairment	13,165		13,165		14,766
Originated loans [Member] | Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	2,345		2,345		858
Collectively evaluated for impairment	6,342		6,342		5,372
Originated loans [Member] | Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	501		501		509
Collectively evaluated for impairment	1,940		1,940		2,054
Originated loans [Member] | Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	1,307		1,307		1,386
Collectively evaluated for impairment	2,399		2,399		2,375
Originated loans [Member] | One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		46
Collectively evaluated for impairment	573		573		591
Originated loans [Member] | Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		792
Collectively evaluated for impairment	379		379		1,339
Originated loans [Member] | Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		658
Collectively evaluated for impairment	530		530		1,527
Originated loans [Member] | Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	39		39		110
Collectively evaluated for impairment	556		556		638
Originated loans [Member] | Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	446		446		870
Purchased other covered loans [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	303		303		81
Collectively evaluated for impairment	101		101		94
Purchased other covered loans [Member] | Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	268		268		4
Collectively evaluated for impairment	11		11		38
Purchased other covered loans [Member] | Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	17		17		29
Purchased other covered loans [Member] | Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	24		24		0
Purchased other covered loans [Member] | One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	35		35		44
Collectively evaluated for impairment	9		9		23
Purchased other covered loans [Member] | Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased other covered loans [Member] | Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased other covered loans [Member] | Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		33
Collectively evaluated for impairment	40		40		4
Purchased other covered loans [Member] | Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased other non-covered loans [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	1,064		1,064		220
Collectively evaluated for impairment	299		299		105
Purchased other non-covered loans [Member] | Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	1,061		1,061		10
Collectively evaluated for impairment	79		79		30
Purchased other non-covered loans [Member] | Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		7
Collectively evaluated for impairment	51		51		40
Purchased other non-covered loans [Member] | Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		18
Collectively evaluated for impairment	44		44		16
Purchased other non-covered loans [Member] | One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		61
Collectively evaluated for impairment	6		6		5
Purchased other non-covered loans [Member] | Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased other non-covered loans [Member] | Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased other non-covered loans [Member] | Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	3		3		124
Collectively evaluated for impairment	119		119		14
Purchased other non-covered loans [Member] | Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Individually evaluated for impairment	0		0		0
Collectively evaluated for impairment	0		0		0
Purchased impaired covered loans [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	5,568		5,568		4,177
Purchased impaired covered loans [Member] | Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	1,134		1,134		1,034
Purchased impaired covered loans [Member] | Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	1,039		1,039		989
Purchased impaired covered loans [Member] | Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	2,140		2,140		1,164
Purchased impaired covered loans [Member] | One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	272		272		210
Purchased impaired covered loans [Member] | Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	846		846		639
Purchased impaired covered loans [Member] | Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	0		0		0
Purchased impaired covered loans [Member] | Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	137		137		141
Purchased impaired covered loans [Member] | Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	0		0		0
Purchased impaired non-covered loans [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	4,063		4,063		4,792
Purchased impaired non-covered loans [Member] | Commercial and industrial [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	2,204		2,204		2,566
Purchased impaired non-covered loans [Member] | Owner-occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	333		333		393
Purchased impaired non-covered loans [Member] | Non-owner occupied commercial real estate [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	342		342		410
Purchased impaired non-covered loans [Member] | One-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	208		208		241
Purchased impaired non-covered loans [Member] | Real estate construction and land development : one-to-four family residential [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	268		268		361
Purchased impaired non-covered loans [Member] | Real estate construction and land development : five or more family residential and commercial properties [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	90		90		124
Purchased impaired non-covered loans [Member] | Consumer [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	618		618		697
Purchased impaired non-covered loans [Member] | Unallocated [Member]
Schedule of allowance for loan losses on the basis of impairment method
Collectively evaluated for impairment	$ 0		$ 0		$ 0