Mergers and Acquisitions - (Details 4) - Heritage Financial Group - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Business Acquisition [Line Items]
Interest income	$ 160,267	$ 149,138
Interest expense	13,056	10,874
Net interest income	147,211	138,264
Provision for loan and lease losses	3,230	2,550
Noninterest income	68,888	71,771
Noninterest expense	147,073	162,862
Income before income taxes	65,796	44,623
Income taxes	21,680	13,883
Net income	$ 44,116	$ 30,740
Earnings per share:
Basic (usd per share)	$ 1.07	$ 0.85
Diluted (usd per share)	$ 1.06	$ 0.85