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

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-12-07</periodOfReport>

    <issuer>
        <issuerCik>0000825313</issuerCik>
        <issuerName>ALLIANCEBERNSTEIN HOLDING L.P.</issuerName>
        <issuerTradingSymbol>AB</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001279325</rptOwnerCik>
            <rptOwnerName>MASTERS SETH J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ALLIANCEBERNSTEIN L.P.</rptOwnerStreet1>
            <rptOwnerStreet2>1345 AVENUE OF THE AMERICAS</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10105</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CIO, Blend Strat. and ABDC</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>units rep. assignments of beneficial owner. of lp interests</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2009-12-07</value>
                <footnoteId id="F2"/>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>108679</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>26.73</value>
                    <footnoteId id="F2"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>118947</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>by rabbi trust under incentive compensation award plan</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Holding Units</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>62584</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Units representing assignments of beneficial ownership of limited partnership interests in AllianceBernstein Holding L.P. (&quot;Holding Units&quot;)</footnote>
        <footnote id="F2">The price set forth in the table is the closing price of a Holding Unit as reported for composite transactions on the New York Stock Exchange on December 7, 2009, the date the award was granted by the Compensation Committee of the Board of Directors of AllianceBernstein Corporation.  This form was not filed within 48 hours of grant date because award amounts were not calculated and communicated to award recipients until the week of December 14, 2009.</footnote>
        <footnote id="F3">Reporting Person's 2009 incentive compensation award was notionally converted into Holding Units.  He therefore may be deemed to have acquired 108,679 Holding Units.  These Holding Units are held in a rabbi trust under the incentive compenation award program until they are distributed to Reporting Person.  The award vests (subject to various agreements and covenants set forth in the award agreement) in equal annual increments on each of December 1, 2010, 2011, 2012 and 2013.</footnote>
        <footnote id="F4">On December 1, 2009, 6,443 Holding Units previously owned by Reporting Person through a rabbi trust under an incentive compensation award program were distributed to him.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Mona Bhalla, by pwr. att'y</signatureName>
        <signatureDate>2009-12-17</signatureDate>
    </ownerSignature>
</ownershipDocument>
