<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2021-01-26</periodOfReport>

    <dateOfOriginalSubmission>2021-01-28</dateOfOriginalSubmission>

    <notSubjectToSection16>false</notSubjectToSection16>

    <issuer>
        <issuerCik>0000764038</issuerCik>
        <issuerName>SOUTH STATE Corp</issuerName>
        <issuerTradingSymbol>SSB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001769689</rptOwnerCik>
            <rptOwnerName>Lapointe Greg A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>1101 FIRST STREET SOUTH, SUITE 202</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>WINTER HAVEN</rptOwnerCity>
            <rptOwnerState>FL</rptOwnerState>
            <rptOwnerZipCode>33880</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>false</isDirector>
            <isOfficer>true</isOfficer>
            <isTenPercentOwner>false</isTenPercentOwner>
            <isOther>false</isOther>
            <officerTitle>Chief Banking Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Share Units</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>72.31</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-01-26</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2021-01-26</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5532.00</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>72.31</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F1"/>
            </exerciseDate>
            <expirationDate>
                <value>2023-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>5532.00</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>5532.00</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Share Units</value>
                <footnoteId id="F2"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>72.31</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-01-26</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2021-01-26</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>false</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness></transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1383.00</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>72.31</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-01-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1383.00</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>19726.00</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Number of Performance Share Units (&quot;PSUs&quot;) awarded on 1/26/21. The awards will vest after the 3-year performance period ending December 31, 2023. The units are exchangeable with the Company's common stock at the exchange rate of 1 for 1 after the vesting date.</footnote>
        <footnote id="F2">Number of time-vested Restricted Share Units (&quot;RSUs&quot;) awarded on 1/26/21. The awards will vest at a rate of one third on each January 26th, 2022, 2023 and 2024. The units are exchangeable with the Company's common stock at the exchange rate of 1 for 1 after the vesting date.</footnote>
        <footnote id="F3">To correct the total number of derivative securities beneficially owned, followed by the RSUs awarded on 1/26/21, originally reported in the Form 4, filed on January 28, 2021.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>William E. Matthews, V, CFO, pursuant to power of attorney</signatureName>
        <signatureDate>2021-02-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
