Loans and the Allowance for Loan Losses - (Details 8) - Receivables Acquired with Deteriorated Credit Quality - USD ($) $ in Thousands		Sep. 30, 2015	Dec. 31, 2014
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		$ 329,922	$ 344,425
Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		20,993	8,004
Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		50,869	135,037
Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		258,060	201,384
Commercial, financial, agricultural
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		12,777	23,404
Commercial, financial, agricultural | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		1,205	0
Commercial, financial, agricultural | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		415	6,684
Commercial, financial, agricultural | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		11,157	16,720
Lease financing
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Lease financing | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Lease financing | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Lease financing | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Real estate – construction
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		1,614	0
Real estate – construction | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Real estate – construction | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		94	0
Real estate – construction | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		1,520	0
Real estate – 1-4 family mortgage
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		91,426	82,819
Real estate – 1-4 family mortgage | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		5,895	420
Real estate – 1-4 family mortgage | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		26,990	43,597
Real estate – 1-4 family mortgage | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		58,541	38,802
Real estate – commercial mortgage
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		221,212	234,245
Real estate – commercial mortgage | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		13,893	7,584
Real estate – commercial mortgage | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		23,323	84,720
Real estate – commercial mortgage | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		183,996	141,941
Installment loans to individuals
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality	[1]	2,893	3,957
Installment loans to individuals | Impaired Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		0	0
Installment loans to individuals | Other Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		47	36
Installment loans to individuals | Not Covered Loans
Loans acquired with deteriorated credit quality
Acquired with deteriorated credit quality		$ 2,846	$ 3,921

[1] Includes lease financing receivables.