Business Combinations, BancTrust Loans and Real Estate Acquired (Details) (BancTrust Financial Group, Inc. [Member], USD $) In Thousands, unless otherwise specified	Feb. 15, 2013
Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	$ 1,134,014
Other real estate	58,083
Total loans and other real estate acquired from BancTrust	1,192,097
Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	181,953
Total loans acquired from BancTrust (In hundredths)	16.00%
Other real estate	16,915
Other real estate (in hundredths)	29.10%
Total loans and other real estate acquired from BancTrust	198,868
Total loans and other real estate acquired from BancTrust (in hundredths)	16.70%
Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	952,061
Other real estate	41,168
Total loans and other real estate acquired from BancTrust	993,229
Commercial and Industrial Loans [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	262,536
Commercial and Industrial Loans [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	25,489
Total loans acquired from BancTrust (In hundredths)	9.70%
Commercial and Industrial Loans [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	237,047
Consumer Loans Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	40,808
Consumer Loans Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	2,152
Total loans acquired from BancTrust (In hundredths)	5.30%
Consumer Loans Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	38,656
Other Loans Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	14,248
Other Loans Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	462
Total loans acquired from BancTrust (In hundredths)	3.20%
Other Loans Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	13,786
Construction Land Development and Other Land Loans [Member] | Real Estate Secured Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	236,237
Construction Land Development and Other Land Loans [Member] | Real Estate Secured Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	100,045
Total loans acquired from BancTrust (In hundredths)	42.30%
Construction Land Development and Other Land Loans [Member] | Real Estate Secured Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	136,192
Secured by 1-4 Family Residential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	216,444
Secured by 1-4 Family Residential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	22,914
Total loans acquired from BancTrust (In hundredths)	10.60%
Secured by 1-4 Family Residential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	193,530
Secured by Nonfarm, Nonresidential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	329,026
Secured by Nonfarm, Nonresidential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	28,140
Total loans acquired from BancTrust (In hundredths)	8.60%
Secured by Nonfarm, Nonresidential Properties [Member] | Real Estate Secured Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	300,886
Other Real Estate Properties [Member] | Real Estate Secured Financing Receivable [Member] | Balance [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	34,715
Other Real Estate Properties [Member] | Real Estate Secured Financing Receivable [Member] | Total Credit Mark [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	2,751
Total loans acquired from BancTrust (In hundredths)	7.90%
Other Real Estate Properties [Member] | Real Estate Secured Financing Receivable [Member] | Fair Value [Member]
Business Acquisition [Line Items]
Total loans acquired from BancTrust	$ 31,964