Regulatory Matters (Details) $ in Thousands	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Capital ratios
Actual. Capital Amount	$ 1,273,547	$ 788,544
Actual, Ratio (as a percent)	11.59%	11.66%
Tier One Common Equity Capital Required to be Well Capitalized	$ 714,221	$ 439,755
Tier One Common Equity Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	6.50	6.50
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Actual, Capital Amount	$ 1,384,433	$ 841,266
Actual, Ratio (as a percent)	12.60%	12.43%
Leverage ratio (as a percent)	10.36%	9.88%
Tier One Risk Based Capital Required to be Well Capitalized	$ 879,042	$ 541,237
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	8.00%	8.00%
Total capital to risk-weighted assets
Actual, Capital Amount	$ 1,432,843	$ 881,957
Capital to Risk Weighted Assets (as a percent)	13.04%	13.04%
Required to be considered well capitalized, Capital Amount	$ 1,098,802	$ 676,546
Required to be considered well capitalized, Ratio (as a percent)	10.00%	10.00%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital	$ 1,384,433	$ 841,266
Tier One Leverage Capital to Average Assets (as a percent)	10.36%	9.88%
Tier One Leverage Capital Required to be Well Capitalized	$ 668,075	$ 425,765
Tier One Leverage Capital Required to be Well Capitalized to Average Assets (as a percent)	5.00%	5.00%
Minimum
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Actual, Ratio (as a percent)	4.50%
Leverage ratio (as a percent)	4.00%
Tier 1 capital to risk-weighted assets (as a percent)	6.00%	4.00%
Total capital to risk-weighted assets
Capital to Risk Weighted Assets (as a percent)	8.00%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital to Average Assets (as a percent)	4.00%
Phased In Member
Capital ratios
Tier One Risk Based Capital Required for Capital Adequacy	$ 631,811	$ 346,730
Tier 1 common equity capital to risk-weighted assets (as a percent)	5.750	5.125
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Leverage ratio (as a percent)		6.625%
Tier One Risk Based Capital Required for Capital Adequacy	$ 796,632	$ 448,212
Tier 1 capital to risk-weighted assets (as a percent)	7.25%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,016,392	$ 583,521
Minimum capital required, Ratio (as a percent)	9.25%	8.625%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital to Average Assets (as a percent)		6.625%
Tier One Leverage Capital Required for Capital Adequacy	$ 534,460	$ 340,612
Minimum capital required, Ratio (as a percent)	4.00%	4.00%
Fully Phased Member
Capital ratios
Tier One Risk Based Capital Required for Capital Adequacy	$ 769,162	$ 473,582
Tier 1 common equity capital to risk-weighted assets (as a percent)	7.00	7.00
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Tier One Risk Based Capital Required for Capital Adequacy	$ 933,982	$ 575,064
Tier 1 capital to risk-weighted assets (as a percent)	8.50%	8.50%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,153,742	$ 710,374
Minimum capital required, Ratio (as a percent)	10.50%	10.50%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital Required for Capital Adequacy	$ 534,460	$ 340,612
Minimum capital required, Ratio (as a percent)	4.00%	4.00%
South State Bank (the Bank)
Capital ratios
Actual. Capital Amount	$ 1,360,603	$ 815,823
Actual, Ratio (as a percent)	12.38%	12.06%
Tier One Common Equity Capital Required to be Well Capitalized	$ 714,143	$ 439,627
Tier One Common Equity Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	6.50	6.50
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Actual, Capital Amount	$ 1,360,603	$ 815,823
Actual, Ratio (as a percent)	12.38%	12.06%
Leverage ratio (as a percent)	10.18%	9.58%
Tier One Risk Based Capital Required to be Well Capitalized	$ 878,945	$ 541,079
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets (as a percent)	8.00%	8.00%
Total capital to risk-weighted assets
Actual, Capital Amount	$ 1,409,014	$ 856,388
Capital to Risk Weighted Assets (as a percent)	12.82%	12.66%
Required to be considered well capitalized, Capital Amount	$ 1,098,681	$ 676,349
Required to be considered well capitalized, Ratio (as a percent)	10.00%	10.00%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital	$ 1,360,603	$ 815,823
Tier One Leverage Capital to Average Assets (as a percent)	10.18%	9.58%
Tier One Leverage Capital Required to be Well Capitalized	$ 667,987	$ 425,604
Tier One Leverage Capital Required to be Well Capitalized to Average Assets (as a percent)	5.00%	5.00%
South State Bank (the Bank) \| Phased In Member
Capital ratios
Tier One Risk Based Capital Required for Capital Adequacy	$ 631,741	$ 346,629
Tier 1 common equity capital to risk-weighted assets (as a percent)	5.750	5.125
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Leverage ratio (as a percent)		6.625%
Tier One Risk Based Capital Required for Capital Adequacy	$ 796,544	$ 448,081
Tier 1 capital to risk-weighted assets (as a percent)	7.25%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,016,280	$ 583,351
Minimum capital required, Ratio (as a percent)	9.25%	8.625%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital to Average Assets (as a percent)		6.625%
Tier One Leverage Capital Required for Capital Adequacy	$ 534,390	$ 340,483
Minimum capital required, Ratio (as a percent)	4.00%	4.00%
South State Bank (the Bank) \| Fully Phased Member
Capital ratios
Tier One Risk Based Capital Required for Capital Adequacy	$ 769,077	$ 473,444
Tier 1 common equity capital to risk-weighted assets (as a percent)	7.00	7.00
Tier One Risk Based Capital to Risk Weighted Assets [Abstract]
Tier One Risk Based Capital Required for Capital Adequacy	$ 933,879	$ 574,896
Tier 1 capital to risk-weighted assets (as a percent)	8.50%	8.50%
Total capital to risk-weighted assets
Minimum capital required, Capital Amount	$ 1,153,615	$ 710,166
Minimum capital required, Ratio (as a percent)	10.50%	10.50%
Tier One Leverage Capital to Average Assets [Abstract]
Tier One Leverage Capital Required for Capital Adequacy	$ 534,390	$ 340,483
Minimum capital required, Ratio (as a percent)	4.00%	4.00%

Tier 1 Common Equity Capital as defined in the regulations.

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The minimum Tier One Common Equity Capital Ratio (Tier one The minimum Tier One Common Equity Capital Ratio (Tier one common equity capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Common Equity Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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