Capital Ratios (Details) - USD ($) $ in Thousands	Jan. 01, 2019	Jun. 30, 2016	Dec. 31, 2015	Jun. 30, 2015
Capital ratios
Capital conversion buffer common equity Tier 1 of risk-weighted assets (as a percent)	2.50%
Common equity Tier 1 to risk-weighted assets
Actual, Capital Amount		$ 741,000	$ 711,577	$ 695,107
Actual, Ratio (as a percent)		11.23%	11.84%	12.16%
Minimum capital required, Ratio (as a percent)		4.50%
Required to be considered well capitalized, Capital Amount		$ 428,792	$ 390,624	$ 372,011
Required to be considered well capitalized, Ratio (as a percent)		6.50%	6.50%	6.50%
Tier I capital to risk-weighted assets
Actual, Capital Amount		$ 793,116	$ 763,590	$ 745,570
Actual, Ratio (as a percent)		12.02%	12.71%	13.03%
Minimum capital required, Ratio (as a percent)		6.00%	4.00%
Required to be considered well capitalized, Capital Amount		$ 527,744	$ 480,768	$ 457,860
Required to be considered well capitalized, Ratio (as a percent)		8.00%	8.00%	8.00%
Total capital to risk-weighted assets
Actual, Capital Amount		$ 834,102	$ 801,745	$ 785,245
Actual, Ratio (as a percent)		12.64%	13.34%	13.72%
Minimum capital required, Ratio (as a percent)		8.00%
Required to be considered well capitalized, Capital Amount		$ 659,681	$ 600,961	$ 572,325
Required to be considered well capitalized, Ratio (as a percent)		10.00%	10.00%	10.00%
Tier I capital to average assets (leverage ratio)
Actual, Capital Amount		$ 793,116	$ 763,590	$ 745,570
Actual, Ratio (as a percent)		9.51%	9.31%	9.68%
Minimum capital required, Ratio (as a percent)		4.00%
Required to be considered well capitalized, Capital Amount		$ 416,984	$ 410,107	$ 385,089
Required to be considered well capitalized, Ratio (as a percent)		5.00%	5.00%	5.00%
Phase-In Schedule
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount		$ 338,086	$ 270,432	$ 257,546
Minimum capital required, Ratio (as a percent)		5.125%	4.50%	4.50%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 395,808	$ 360,576	$ 343,395
Minimum capital required, Ratio (as a percent)		6.00%	6.00%	6.00%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 527,744	$ 480,768	$ 457,860
Minimum capital required, Ratio (as a percent)		8.00%	8.00%	8.00%
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount		$ 333,587	$ 328,085	$ 308,071
Minimum capital required, Ratio (as a percent)		4.00%	4.00%	4.00%
Fully Phased-In
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount		$ 461,776	$ 420,762	$ 400,628
Minimum capital required, Ratio (as a percent)		7.00%	7.00%	7.00%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 560,728	$ 510,817	$ 486,476
Minimum capital required, Ratio (as a percent)		8.50%	8.50%	8.50%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 692,665	$ 631,009	$ 600,941
Minimum capital required, Ratio (as a percent)		10.50%	10.50%	10.50%
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount		$ 333,587	$ 328,085	$ 308,071
Minimum capital required, Ratio (as a percent)		4.00%	4.00%	4.00%
South State Bank (the Bank)
Common equity Tier 1 to risk-weighted assets
Actual, Capital Amount		$ 766,183	$ 740,532	$ 725,545
Actual, Ratio (as a percent)		11.62%	12.33%	12.68%
Required to be considered well capitalized, Capital Amount		$ 428,647	$ 390,511	$ 371,874
Required to be considered well capitalized, Ratio (as a percent)		6.50%	6.50%	6.50%
Tier I capital to risk-weighted assets
Actual, Capital Amount		$ 766,183	$ 740,532	$ 725,545
Actual, Ratio (as a percent)		11.62%	12.33%	12.68%
Required to be considered well capitalized, Capital Amount		$ 527,566	$ 480,629	$ 457,692
Required to be considered well capitalized, Ratio (as a percent)		8.00%	8.00%	8.00%
Total capital to risk-weighted assets
Actual, Capital Amount		$ 807,084	$ 778,538	$ 765,221
Actual, Ratio (as a percent)		12.24%	12.96%	13.38%
Required to be considered well capitalized, Capital Amount		$ 659,457	$ 600,786	$ 572,115
Required to be considered well capitalized, Ratio (as a percent)		10.00%	10.00%	10.00%
Tier I capital to average assets (leverage ratio)
Actual, Capital Amount		$ 766,183	$ 740,532	$ 725,545
Actual, Ratio (as a percent)		9.19%	9.03%	9.43%
Required to be considered well capitalized, Capital Amount		$ 416,791	$ 409,818	$ 384,851
Required to be considered well capitalized, Ratio (as a percent)		5.00%	5.00%	5.00%
South State Bank (the Bank) | Phase-In Schedule
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount		$ 337,972	$ 270,354	$ 257,452
Minimum capital required, Ratio (as a percent)		5.125%	4.50%	4.50%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 395,674	$ 360,471	$ 343,269
Minimum capital required, Ratio (as a percent)		6.00%	6.00%	6.00%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 527,566	$ 480,629	$ 457,692
Minimum capital required, Ratio (as a percent)		8.00%	8.00%	8.00%
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount		$ 333,433	$ 327,854	$ 307,881
Minimum capital required, Ratio (as a percent)		4.00%	4.00%	4.00%
South State Bank (the Bank) | Fully Phased-In
Common equity Tier 1 to risk-weighted assets
Minimum capital required, Capital Amount		$ 461,620	$ 420,550	$ 400,480
Minimum capital required, Ratio (as a percent)		7.00%	7.00%	7.00%
Tier I capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 560,539	$ 510,668	$ 486,297
Minimum capital required, Ratio (as a percent)		8.50%	8.50%	8.50%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount		$ 692,430	$ 630,825	$ 600,720
Minimum capital required, Ratio (as a percent)		10.50%	10.50%	10.50%
Tier I capital to average assets (leverage ratio)
Minimum capital required, Capital Amount		$ 333,433	$ 327,854	$ 307,881
Minimum capital required, Ratio (as a percent)		4.00%	4.00%	4.00%