Loans and Allowance for Loan Losses (Details 7) (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:
Provision for loan losses before benefit attributable to FDIC loss share agreements	$ 109	$ (175)	$ 27	$ 10,708
Benefit attributable to FDIC loss share agreements	550	4,219	1,871	700
Total provision for loan losses charged to operations	659	4,044	1,898	11,408
Provision for loan losses recorded through the FDIC loss share receivable	(550)	(4,219)	(1,871)	(700)
Acquired loans
Allowance for loan losses:
Balance at the beginning of the period	31,597	35,813	32,132	31,620
Provision for loan losses before benefit attributable to FDIC loss share agreements	(456)	(4,675)	(991)	(482)
Benefit attributable to FDIC loss share agreements	550	4,219	1,871	700
Total provision for loan losses charged to operations	94	(456)	880	218
Provision for loan losses recorded through the FDIC loss share receivable	(550)	(4,219)	(1,871)	(700)
Balance at the end of the period	31,141	31,138	31,141	31,138
Loans collectively evaluated for impairment	31,141	31,138	31,141	31,138
Loans:
Loans collectively evaluated for impairment	1,347,770	520,991	1,347,770	520,991
Total acquired loans	3,013,103	520,991	3,013,103	520,991	1,074,742
Acquired loans | Commercial Loans Greater Than or Equal to $1 Million-CBT
Allowance for loan losses:
Balance at the beginning of the period	13,428	16,871	15,408	16,706
Provision for loan losses before benefit attributable to FDIC loss share agreements	(1,283)	(1,059)	(3,263)	(894)
Benefit attributable to FDIC loss share agreements	1,220	1,006	3,100	814
Total provision for loan losses charged to operations	(63)	(53)	(163)	(80)
Provision for loan losses recorded through the FDIC loss share receivable	(1,220)	(1,006)	(3,100)	(814)
Balance at the end of the period	12,145	15,812	12,145	15,812
Loans collectively evaluated for impairment	12,145	15,812	12,145	15,812
Loans:
Loans collectively evaluated for impairment	37,894	53,301	37,894	53,301
Total acquired loans	37,894	53,301	37,894	53,301
Acquired loans | Commercial Real Estate
Allowance for loan losses:
Balance at the beginning of the period	821	1,812	1,517	1,318
Provision for loan losses before benefit attributable to FDIC loss share agreements	330	(1,365)	(366)	(871)
Benefit attributable to FDIC loss share agreements	(264)	1,296	240	819
Total provision for loan losses charged to operations	66	(69)	(126)	(52)
Provision for loan losses recorded through the FDIC loss share receivable	264	(1,296)	(240)	(819)
Balance at the end of the period	1,151	447	1,151	447
Loans collectively evaluated for impairment	1,151	447	1,151	447
Loans:
Loans collectively evaluated for impairment	477,968	151,444	477,968	151,444
Total acquired loans	477,968	151,444	477,968	151,444
Acquired loans | Commercial Real Estate - Construction and Development
Allowance for loan losses:
Balance at the beginning of the period	4,392	3,238	1,628
Provision for loan losses before benefit attributable to FDIC loss share agreements	(39)	(1,744)	2,725	1,494
Benefit attributable to FDIC loss share agreements	31	1,415	(2,067)	(1,268)
Total provision for loan losses charged to operations	(8)	(329)	658	226
Provision for loan losses recorded through the FDIC loss share receivable	(31)	(1,415)	2,067	1,268
Balance at the end of the period	4,353	1,494	4,353	1,494
Loans collectively evaluated for impairment	4,353	1,494	4,353	1,494
Loans:
Loans collectively evaluated for impairment	132,176	58,317	132,176	58,317
Total acquired loans	132,176	58,317	132,176	58,317
Acquired loans | Residential Real Estate
Allowance for loan losses:
Balance at the beginning of the period	5,150	4,415	4,616	5,471
Provision for loan losses before benefit attributable to FDIC loss share agreements	488	41	1,019	(1,015)
Benefit attributable to FDIC loss share agreements	(392)	(39)	(494)	1,091
Total provision for loan losses charged to operations	96	2	525	76
Provision for loan losses recorded through the FDIC loss share receivable	392	39	494	(1,091)
Balance at the end of the period	5,638	4,456	5,638	4,456
Loans collectively evaluated for impairment	5,638	4,456	5,638	4,456
Loans:
Loans collectively evaluated for impairment	505,127	205,441	505,127	205,441
Total acquired loans	505,127	205,441	505,127	205,441
Acquired loans | Consumer
Allowance for loan losses:
Balance at the beginning of the period	474	73	96
Provision for loan losses before benefit attributable to FDIC loss share agreements	(2)	16	379	89
Benefit attributable to FDIC loss share agreements	1	(14)	(320)	(71)
Total provision for loan losses charged to operations	(1)	2	59	18
Provision for loan losses recorded through the FDIC loss share receivable	(1)	14	320	71
Balance at the end of the period	472	89	472	89
Loans collectively evaluated for impairment	472	89	472	89
Loans:
Loans collectively evaluated for impairment	108,420	10,125	108,420	10,125
Total acquired loans	108,420	10,125	108,420	10,125
Acquired loans | Commercial & Industrial
Allowance for loan losses:
Balance at the beginning of the period	2,953	4,749	4,305	4,564
Provision for loan losses before benefit attributable to FDIC loss share agreements	(55)	(478)	(1,407)	(293)
Benefit attributable to FDIC loss share agreements	53	473	1,337	271
Total provision for loan losses charged to operations	(2)	(5)	(70)	(22)
Provision for loan losses recorded through the FDIC loss share receivable	(53)	(473)	(1,337)	(271)
Balance at the end of the period	2,898	4,271	2,898	4,271
Loans collectively evaluated for impairment	2,898	4,271	2,898	4,271
Loans:
Loans collectively evaluated for impairment	81,734	37,499	81,734	37,499
Total acquired loans	81,734	37,499	81,734	37,499
Acquired loans | Single Pay
Allowance for loan losses:
Balance at the beginning of the period	4,379	4,655	4,562	3,561
Provision for loan losses before benefit attributable to FDIC loss share agreements	105	(86)	(78)	1,008
Benefit attributable to FDIC loss share agreements	(99)	82	75	(956)
Total provision for loan losses charged to operations	6	(4)	(3)	52
Provision for loan losses recorded through the FDIC loss share receivable	99	(82)	(75)	956
Balance at the end of the period	4,484	4,569	4,484	4,569
Loans collectively evaluated for impairment	4,484	4,569	4,484	4,569
Loans:
Loans collectively evaluated for impairment	4,451	4,864	4,451	4,864
Total acquired loans	$ 4,451	$ 4,864	$ 4,451	$ 4,864