Loans and Asset Quality Information (Details 9) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Provisions	$ 79,672	$ 41,301	$ 54,562
Ending balance - total	2,094,143	2,069,152
Commercial, financial and agricultural
Beginning balance	3,780	4,731
Charge-offs	(4,912)	(2,703)
Recoveries	354	389
Provisions	5,465	1,363
Ending balance	4,687	3,780
Individually evaluated for impairment		60
Collectively evaluated for impairment	4,687	3,720
Loans acquired with deteriorated credit quality
Ending balance - total	170,741	172,357
Individually evaluated for impairment		2,526
Collectively evaluated for impairment	170,741	169,832
Loans acquired with deteriorated credit quality
RealEstateConstructionMember
Beginning balance	11,306	12,520
Charge-offs	(19,312)	(16,240)
Recoveries	986	1,142
Provisions	19,876	13,884
Ending balance	12,856	11,306
Individually evaluated for impairment		607
Collectively evaluated for impairment	12,856	10,699
Loans acquired with deteriorated credit quality
Ending balance - total	218,108	246,805
Individually evaluated for impairment	4,276	34,750
Collectively evaluated for impairment	213,832	212,055
Loans acquired with deteriorated credit quality		920
Real estate residential, farmland and mutli-family
Beginning balance	13,532	11,283
Charge-offs	(20,879)	(9,045)
Recoveries	430	719
Provisions	20,999	10,575
Ending balance	14,082	13,532
Individually evaluated for impairment	50	150
Collectively evaluated for impairment	14,032	13,382
Loans acquired with deteriorated credit quality
Ending balance - total	819,439	795,655
Individually evaluated for impairment	1,705	11,880
Collectively evaluated for impairment	817,734	783,775
Loans acquired with deteriorated credit quality
Real estate home equity lines of credit
Beginning balance	1,690	3,634
Charge-offs	(3,287)	(1,147)
Recoveries	209	107
Provisions	3,272	(904)
Ending balance	1,884	1,690
Individually evaluated for impairment
Collectively evaluated for impairment	1,884	1,690
Loans acquired with deteriorated credit quality
Ending balance - total	200,880	207,436
Individually evaluated for impairment		527
Collectively evaluated for impairment	200,880	206,909
Loans acquired with deteriorated credit quality
Real estate commercial
Beginning balance	3,414	3,972
Charge-offs	(16,616)	(3,355)
Recoveries	333	37
Provisions	18,116	2,760
Ending balance	5,247	3,414
Individually evaluated for impairment	957	200
Collectively evaluated for impairment	4,290	3,214
Loans acquired with deteriorated credit quality
Ending balance - total	627,940	587,183
Individually evaluated for impairment	15,040	30,846
Collectively evaluated for impairment	612,900	556,337
Loans acquired with deteriorated credit quality
Consumer
Beginning balance	1,872	1,961
Charge-offs	(1,539)	(845)
Recoveries	273	182
Provisions	1,333	574
Ending balance	1,939	1,872
Individually evaluated for impairment
Collectively evaluated for impairment	1,939	1,872
Loans acquired with deteriorated credit quality
Ending balance - total	55,711	58,436
Individually evaluated for impairment		12
Collectively evaluated for impairment	55,711	58,424
Loans acquired with deteriorated credit quality
Unallocated
Beginning balance	16	174
Charge-offs		(524)
Recoveries		93
Provisions	932	273
Ending balance	948	16
Individually evaluated for impairment
Collectively evaluated for impairment	948	16
Loans acquired with deteriorated credit quality
Ending balance - total
Individually evaluated for impairment
Collectively evaluated for impairment
Loans acquired with deteriorated credit quality
Non-covered
Beginning balance	35,610	38,275
Charge-offs	(66,545)	(33,859)
Recoveries	2,585	2,669
Provisions	69,993	28,525
Ending balance	41,643	35,610
Individually evaluated for impairment	1,007	1,017
Collectively evaluated for impairment	40,636	34,593
Loans acquired with deteriorated credit quality
Ending balance - total	2,092,819	2,067,872
Individually evaluated for impairment	21,021	80,541
Collectively evaluated for impairment	2,071,798	1,987,331
Loans acquired with deteriorated credit quality		920
Non-covered | RealEstateConstructionMember
Ending balance - total	218,108	246,805
Non-covered | Real estate residential, farmland and mutli-family
Ending balance - total	819,439	795,655
Non-covered | Real estate home equity lines of credit
Ending balance - total	200,880	207,436
Non-covered | Real estate commercial
Ending balance - total	627,940	587,183
Non-covered | Consumer
Ending balance - total	$ 55,711	$ 58,436