Loans and Allowance for Loan Losses (Details 6) (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
Allowance for loan losses:
Charge-offs	$ (4,293)	$ (5,940)	$ (12,121)	$ (17,193)
Recoveries	1,248	610	2,870	3,075
Provision	659	4,044	1,898	11,408
Non-acquired loans
Allowance for loan losses:
Balance at the beginning of the period	38,625	47,269	44,378	49,367
Charge-offs	(4,293)	(5,940)	(12,121)	(17,193)
Recoveries	1,248	610	2,870	3,075
Provision	565	4,500	1,018	11,190
Balance at the end of the period	36,145	46,439	36,145	46,439
Loans individually evaluated for impairment	1,301	2,572	1,301	2,572
Loans collectively evaluated for impairment	34,844	43,867	34,844	43,867
Loans:
Loans individually evaluated for impairment	29,584	44,043	29,584	44,043
Loans collectively evaluated for impairment	2,711,658	2,473,309	2,711,658	2,473,309
Total loans	2,741,242	2,517,352	2,741,242	2,517,352	2,571,003
Non-acquired loans | Construction & Land Development
Allowance for loan losses:
Balance at the beginning of the period	8,431	12,267	10,836	12,373
Charge-offs	(1,244)	(3,441)	(4,457)	(7,073)
Recoveries	650	187	1,043	1,213
Provision	(108)	2,480	307	4,980
Balance at the end of the period	7,729	11,493	7,729	11,493
Loans individually evaluated for impairment	558	1,151	558	1,151
Loans collectively evaluated for impairment	7,171	10,340	7,171	10,340
Loans:
Loans individually evaluated for impairment	8,201	12,680	8,201	12,680
Loans collectively evaluated for impairment	279,998	260,926	279,998	260,926
Total loans	288,199	273,606	288,199	273,606	273,420
Non-acquired loans | Commercial Non-owner Occupied
Allowance for loan losses:
Balance at the beginning of the period	4,866	5,432	4,921	6,109
Charge-offs	(652)	(504)	(652)	(1,877)
Recoveries	18	126	345	222
Provision	(462)	556	(844)	1,156
Balance at the end of the period	3,770	5,610	3,770	5,610
Loans individually evaluated for impairment		676		676
Loans collectively evaluated for impairment	3,770	4,935	3,770	4,935
Loans:
Loans individually evaluated for impairment	2,804	7,121	2,804	7,121
Loans collectively evaluated for impairment	279,874	271,814	279,874	271,814
Total loans	282,678	278,935	282,678	278,935	290,071
Non-acquired loans | Commercial Owner Occupied
Allowance for loan losses:
Balance at the beginning of the period	7,984	9,476	8,743	10,356
Charge-offs	(219)	(334)	(1,622)	(2,009)
Recoveries	1		16	2
Provision	(53)	393	576	1,186
Balance at the end of the period	7,713	9,535	7,713	9,535
Loans individually evaluated for impairment	19	402	19	402
Loans collectively evaluated for impairment	7,694	9,134	7,694	9,134
Loans:
Loans individually evaluated for impairment	14,683	18,377	14,683	18,377
Loans collectively evaluated for impairment	799,576	769,246	799,576	769,246
Total loans	814,259	787,623	814,259	787,623	784,152
Non-acquired loans | Consumer Owner Occupied
Allowance for loan losses:
Balance at the beginning of the period	6,438	7,617	6,568	7,453
Charge-offs	(888)	(545)	(1,276)	(1,850)
Recoveries	104	24	234	44
Provision	448	681	576	2,130
Balance at the end of the period	6,102	7,777	6,102	7,777
Loans individually evaluated for impairment	21	218	21	218
Loans collectively evaluated for impairment	6,081	7,559	6,081	7,559
Loans:
Loans individually evaluated for impairment	575	2,613	575	2,613
Loans collectively evaluated for impairment	498,159	428,212	498,159	428,212
Total loans	498,734	430,825	498,734	430,825	434,503
Non-acquired loans | Home Equity
Allowance for loan losses:
Balance at the beginning of the period	2,974	3,992	3,626	4,269
Charge-offs	(206)	(203)	(868)	(1,251)
Recoveries	75	54	174	460
Provision	91		2	365
Balance at the end of the period	2,934	3,843	2,934	3,843
Loans collectively evaluated for impairment	2,934	3,843	2,934	3,843
Loans:
Loans collectively evaluated for impairment	255,291	255,677	255,291	255,677
Total loans	255,291	255,677	255,291	255,677	255,284
Non-acquired loans | Commercial & Industrial
Allowance for loan losses:
Balance at the beginning of the period	4,039	3,765	4,939	3,901
Charge-offs	(154)	(270)	(781)	(705)
Recoveries	187	19	324	201
Provision	(301)	260	(711)	377
Balance at the end of the period	3,771	3,774	3,771	3,774
Loans collectively evaluated for impairment	3,771	3,774	3,771	3,774
Loans:
Loans individually evaluated for impairment	707	474	707	474
Loans collectively evaluated for impairment	301,138	244,811	301,138	244,811
Total loans	301,845	245,285	301,845	245,285	279,763
Non-acquired loans | Other Income Producing Property
Allowance for loan losses:
Balance at the beginning of the period	3,260	3,410	3,747	3,636
Charge-offs	(179)	(84)	(652)	(824)
Recoveries	12	52	123	347
Provision	(58)	23	(183)	242
Balance at the end of the period	3,035	3,401	3,035	3,401
Loans individually evaluated for impairment	703	125	703	125
Loans collectively evaluated for impairment	2,332	3,276	2,332	3,276
Loans:
Loans individually evaluated for impairment	2,614	2,778	2,614	2,778
Loans collectively evaluated for impairment	137,410	129,054	137,410	129,054
Total loans	140,024	131,832	140,024	131,832	133,713
Non-acquired loans | Consumer
Allowance for loan losses:
Balance at the beginning of the period	426	1,064	781	1,145
Charge-offs	(751)	(523)	(1,813)	(1,454)
Recoveries	201	148	611	575
Provision	955	105	1,252	528
Balance at the end of the period	831	794	831	794
Loans collectively evaluated for impairment	831	794	831	794
Loans:
Loans collectively evaluated for impairment	116,312	86,729	116,312	86,729
Total loans	116,312	86,729	116,312	86,729	86,934
Non-acquired loans | Other Loans
Allowance for loan losses:
Balance at the beginning of the period	207	246	217	125
Charge-offs		(36)		(150)
Recoveries				11
Provision	53	2	43	226
Balance at the end of the period	260	212	260	212
Loans collectively evaluated for impairment	260	212	260	212
Loans:
Loans collectively evaluated for impairment	43,900	26,840	43,900	26,840
Total loans	$ 43,900	$ 26,840	$ 43,900	$ 26,840	$ 33,163