Loans and the Allowance for Loan Losses (Details 8) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013		Dec. 31, 2012
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	$ 482,080		$ 248,029
Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	25,319		31,904
Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	170,693		205,184
Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	286,068		10,941
Commercial, financial, agricultural [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	36,481		11,140
Commercial, financial, agricultural [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Commercial, financial, agricultural [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	10,295		10,800
Commercial, financial, agricultural [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	26,186		340
Lease financing [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Lease financing [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Lease financing [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Lease financing [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Real estate - construction [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	5,883		1,648
Real estate - construction [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Real estate - construction [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	1,648		1,648
Real estate - construction [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	4,235		0
Real estate - 1-4 family mortgage [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	108,333		75,147
Real estate - 1-4 family mortgage [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	1,040		6,122
Real estate - 1-4 family mortgage [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	55,683		67,326
Real estate - 1-4 family mortgage [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	51,610		1,699
Real estate - commercial mortgage [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	323,863		157,869
Real estate - commercial mortgage [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	24,279		25,782
Real estate - commercial mortgage [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	103,036		125,379
Real estate - commercial mortgage [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	196,548		6,708
Installment loans to individuals [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	7,520	[1]	2,225	[1]
Installment loans to individuals [Member] | Impaired Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	0		0
Installment loans to individuals [Member] | Other Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	31		31
Installment loans to individuals [Member] | Not Covered Loans [Member]
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	$ 7,489		$ 2,194

[1] Includes lease financing receivables.