Acquired Loans - Schedule of Covered and Noncovered Acquired Loans by Type (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	$ 390,411	$ 549,409
Less allowance for loan losses, acquired loans	67,619	69,616
Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	372,711	525,783
Less allowance for loan losses, acquired loans	11,259	10,541
Net acquired loans	361,452	515,242
Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	17,700	23,626
Less allowance for loan losses, acquired loans	733	1,518
Net acquired loans	16,967	22,108
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	41,623	58,309
Construction, Land Development and Other Land [Member] | Loans Secured by Real Estate [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	1,021	1,197
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	86,950	116,920
Secured by 1-4 Family Residential Properties [Member] | Loans Secured by Real Estate [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	10,058	13,180
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	135,626	202,323
Secured by Nonfarm, Nonresidential Properties [Member] | Loans Secured by Real Estate [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	4,638	7,672
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	23,860	27,813
Other Real Estate Secured [Member] | Loans Secured by Real Estate [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	1,286	1,096
Commercial and Industrial Loans [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	55,075	88,256
Commercial and Industrial Loans [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	624	277
Consumer Loans [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	5,641	9,772
Consumer Loans [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans		0
Other Loans [Member] | Noncovered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	23,936	22,390
Other Loans [Member] | Covered Loans [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Acquired loans	$ 73	$ 204