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    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_1">
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            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_2">
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            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_3">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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                    <dei:lineNo>3</dei:lineNo>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_4">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_5">
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            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <context id="offrl_7">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001576280</identifier>
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        <period>
            <startDate>2026-07-28</startDate>
            <endDate>2026-07-28</endDate>
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    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-466">S-3</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-467">S-3ASR</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-468">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-469">0001576280</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-470">Guardant Health, Inc.</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
    <ffd:CombinedProspectusTableNa contextRef="rc" id="hiddenrcCombinedProspectusTableNa">N/A</ffd:CombinedProspectusTableNa>
    <ffd:FormTp contextRef="rc" id="ixv-552">S-3</ffd:FormTp>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-553">Guardant Health, Inc.</dei:EntityRegistrantName>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-554">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_1" id="ixv-555">Debt</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_1" id="ixv-556">Debt securities </ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_1" id="ixv-557">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-558"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_2" id="ixv-559">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_2" id="ixv-560">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_2" id="ixv-561">Common Stock </ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_2" id="ixv-562">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_2"
      decimals="7"
      id="ixv-563"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_3" id="ixv-564">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_3" id="ixv-565">Equity</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_3" id="ixv-566">Preferred Stock </ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_3" id="ixv-567">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_3"
      decimals="7"
      id="ixv-568"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_4" id="ixv-569">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_4" id="ixv-570">Other</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_4" id="ixv-571">Depositary Shares </ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_4" id="ixv-572">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_4"
      decimals="7"
      id="ixv-573"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_5" id="ixv-574">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_5" id="ixv-575">Other</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_5" id="ixv-576">Purchase Contracts </ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_5" id="ixv-577">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_5"
      decimals="7"
      id="ixv-578"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_6" id="ixv-579">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_6" id="ixv-580">Other</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_6" id="ixv-581">Units</ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_6" id="ixv-582">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_6"
      decimals="7"
      id="ixv-583"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:PrevslyPdFlg contextRef="offrl_7" id="ixv-584">false</ffd:PrevslyPdFlg>
    <ffd:OfferingSctyTp contextRef="offrl_7" id="ixv-585">Other</ffd:OfferingSctyTp>
    <ffd:OfferingSctyTitl contextRef="offrl_7" id="ixv-586">Warrants</ffd:OfferingSctyTitl>
    <ffd:Rule457rFlg contextRef="offrl_7" id="ixv-587">true</ffd:Rule457rFlg>
    <ffd:FeeRate
      contextRef="offrl_7"
      decimals="7"
      id="ixv-588"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:TtlOfferingAmt contextRef="rc" decimals="2" id="ixv-589" unitRef="USD">0.00</ffd:TtlOfferingAmt>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-590" unitRef="USD">0.00</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-591" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-592" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-593" unitRef="USD">0.00</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-594">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_2" id="ixv-595">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_3" id="ixv-596">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_4" id="ixv-597">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units. (C) Each depositary share will be issued under a deposit agreement.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_5" id="ixv-598">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units. (C) The purchase contracts may be issued under a purchase contract agreement and may obligate us to sell to the holders of such contracts, or vice versa, common stock, preferred stock, debt securities or debt obligations of third parties.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_6" id="ixv-599">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units. (C) The units may be issued under a unit agreement and will represent an interest in one or more securities registered under this registration statement including shares of common stock, preferred stock, debt securities, depositary shares, warrants or purchase contracts, in any combination, which may or may not be separable from one another.</ffd:OfferingNote>
    <ffd:OfferingNote contextRef="offrl_7" id="ixv-600">(A) Deferred in reliance upon Rules 456(b) and 457(r) under the Securities Act of 1933, as amended. The registrant will calculate the registration fee applicable to an offer of securities pursuant to this registration statement based on the fee payment rate in effect on the date of such fee payment. (B) An indeterminate number of the securities of each identified class is being registered as may from time to time be offered at indeterminate prices, including an indeterminate number or amount of securities that may be issued upon settlement, exercise, conversion or exchange of securities offered hereunder, that are represented by depositary shares or pursuant to anti-dilution provisions. Separate consideration may or may not be received for securities that are issuable upon settlement, exercise, conversion or exchange of other securities or that are issued in units. (C) The warrants covered by this registration statement may be warrants to purchase debt securities, common stock, preferred stock or depositary shares of the registrant.</ffd:OfferingNote>
</xbrl>
