Mergers and Acquisitions - (Details 4) - Heritage Financial Group - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Business Acquisition [Line Items]
Interest income	$ 243,299	$ 225,985
Interest expense	20,357	16,680
Net interest income	222,942	209,305
Provision for loan and lease losses	5,880	3,300
Noninterest income	107,160	103,778
Noninterest expense	223,541	238,651
Income before income taxes	100,681	71,132
Income taxes	33,386	22,610
Net income	$ 67,295	$ 48,522
Earnings per share:
Basic (usd per share)	$ 1.61	$ 1.12
Diluted (usd per share)	$ 1.60	$ 1.12