Condensed Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Southeastern Bank Financial Common Stock 2004 Buyback Plan [Member]	Southeastern Bank Financial Surplus 2004 Buyback Plan [Member]	Southeastern Bank Financial 2004 Buyback Plan [Member]	Park Sterling Corporation Common Stock	Park Sterling Corporation Surplus	Park Sterling Corporation	Common Stock 2004 Buyback Plan [Member]	Common Stock Other Than 2004 Buyback Plan	Common Stock	Surplus 2004 Buyback Plan [Member]	Surplus Other Than 2004 Buyback Plan	Surplus	Retained Earnings	Accumulated Other Comprehensive Income (Loss).	2004 Buyback Plan [Member]	Other Than 2004 Buyback Plan	Total
Balance at Dec. 31, 2014									$ 60,377			$ 701,764	$ 223,156	$ (377)			$ 984,920
Balance (in shares) at Dec. 31, 2014									24,150,702
Increase (Decrease) in Stockholders' Equity
Other Comprehensive Income, net of tax effects														(3,494)			(3,494)
Total Comprehensive income																	95,979
Net income													99,473				99,473
Cash dividends declared on common stock per share													(23,710)				(23,710)
Employee stock purchases									$ 34			874					908
Employee stock purchases (in shares)									13,536
Stock options exercised									$ 89			1,026					1,115
Stock options exercised (in shares)									35,360
Restricted stock awards									$ 110			(110)
Restricted stock awards (in shares)									44,105
Common stock repurchased							$ (150)	$ (53)		$ (4,119)	$ (1,309)				$ (4,269)	$ (1,362)	$ (4,300)
Common stock repurchased (in shares)							(60,000)	(21,046)									(60,000)
Share-based compensation expense												5,803					$ 5,803
Balance at Dec. 31, 2015									$ 60,407			703,929	298,919	(3,871)			1,059,384
Balance (in shares) at Dec. 31, 2015									24,162,657
Increase (Decrease) in Stockholders' Equity
Other Comprehensive Income, net of tax effects														(4,340)			(4,340)
Total Comprehensive income																	96,942
Net income													101,282				101,282
Cash dividends declared on common stock per share													(29,285)				(29,285)
Employee stock purchases									$ 36			889					925
Employee stock purchases (in shares)									14,516
Stock options exercised									$ 158			2,046					2,204
Stock options exercised (in shares)									63,527
Restricted stock awards									$ 106			(106)
Restricted stock awards (in shares)									42,226
Stock issued pursuant to restricted stock units.									$ 90			(90)
Stock issued pursuant to restricted stock units (in shares)									35,903
Excess tax benefits in connection with equity awards												4,178					4,178
Value of common stock repurchased buyback plan							$ (82)	$ (139)		$ (2,048)	(3,712)				$ (2,130)	(3,851)
Common stock repurchased buyback plan (in shares)							(32,900)	(55,537)
Share-based compensation expense												6,221					6,221
Balance at Dec. 31, 2016									$ 60,576			711,307	370,916	(8,211)			$ 1,134,588
Balance (in shares) at Dec. 31, 2016									24,230,392								24,230,392
Balance (in shares) Preferred Stock at Dec. 31, 2016																	0
Increase (Decrease) in Stockholders' Equity
Other Comprehensive Income, net of tax effects														(2,216)			$ (2,216)
Total Comprehensive income																	85,338
Net income													87,554				87,554
Cash dividends declared on common stock per share													(38,623)				(38,623)
Employee stock purchases									$ 32			1,023					1,055
Employee stock purchases (in shares)									12,798
Stock options exercised									$ 149			1,816					1,965
Stock options exercised (in shares)									59,480
Common stock issued for acquisition	$ 12,446	$ 422,163	$ 434,609	$ 18,701	$ 669,865	$ 688,566
Common stock issued for acquisition (in shares)	(4,978,338)			7,480,343
Restricted stock awards									$ 53			(53)
Restricted stock awards (in shares)									21,628
Stock issued pursuant to restricted stock units.									$ 95			(95)
Stock issued pursuant to restricted stock units (in shares)									37,802
Common stock repurchased								$ (153)			$ (5,359)					$ (5,512)
Common stock repurchased (in shares)								(61,125)
Share-based compensation expense												6,934					6,934
Balance at Dec. 31, 2017									$ 91,899			$ 1,807,601	$ 419,847	$ (10,427)			$ 2,308,920
Balance (in shares) at Dec. 31, 2017									36,759,656								36,759,656
Balance (in shares) Preferred Stock at Dec. 31, 2017																	0