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  xmlns="http://www.xbrl.org/2003/instance"
  xmlns:dei="http://xbrl.sec.gov/dei/2026"
  xmlns:ffd="http://xbrl.sec.gov/ffd/2026"
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      xlink:href="https://xbrl.sec.gov/ffd/2026/ffd-2026.xsd"
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    <context id="rc">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001451505</identifier>
        </entity>
        <period>
            <startDate>2026-05-15</startDate>
            <endDate>2026-05-15</endDate>
        </period>
    </context>
    <context id="offrl_1">
        <entity>
            <identifier scheme="http://www.sec.gov/CIK">0001451505</identifier>
            <segment>
                <xbrldi:typedMember dimension="ffd:OfferingAxis">
                    <dei:lineNo>1</dei:lineNo>
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        </entity>
        <period>
            <startDate>2026-05-15</startDate>
            <endDate>2026-05-15</endDate>
        </period>
    </context>
    <unit id="USD">
        <measure>iso4217:USD</measure>
    </unit>
    <unit id="pure">
        <measure>pure</measure>
    </unit>
    <ffd:FormTp contextRef="rc" id="ixv-150">SC 14A</ffd:FormTp>
    <ffd:SubmissnTp contextRef="rc" id="ixv-151">PREM14A</ffd:SubmissnTp>
    <ffd:FeeExhibitTp contextRef="rc" id="ixv-152">EX-FILING FEES</ffd:FeeExhibitTp>
    <dei:EntityCentralIndexKey contextRef="rc" id="ixv-153">0001451505</dei:EntityCentralIndexKey>
    <dei:EntityRegistrantName contextRef="rc" id="ixv-154">Transocean Ltd.</dei:EntityRegistrantName>
    <ffd:OfferingTableNa contextRef="rc" id="hiddenrcOfferingTableNa" xsi:nil="true"/>
    <ffd:OffsetTableNa contextRef="rc" id="hiddenrcOffsetTableNa">N/A</ffd:OffsetTableNa>
    <ffd:Rule011Flg contextRef="offrl_1" id="ixv-157">true</ffd:Rule011Flg>
    <ffd:PrevslyPdFlg contextRef="offrl_1" id="ixv-182">false</ffd:PrevslyPdFlg>
    <ffd:TxValtn
      contextRef="offrl_1"
      decimals="2"
      id="ixv-183"
      unitRef="USD">7552236445.65</ffd:TxValtn>
    <ffd:FeeRate
      contextRef="offrl_1"
      decimals="7"
      id="ixv-184"
      unitRef="pure">0.0001381</ffd:FeeRate>
    <ffd:FeeAmt
      contextRef="offrl_1"
      decimals="2"
      id="ixv-185"
      unitRef="USD">1042963.85</ffd:FeeAmt>
    <ffd:TtlTxValtn contextRef="rc" decimals="2" id="ixv-186" unitRef="USD">7552236445.65</ffd:TtlTxValtn>
    <ffd:TtlFeeAmt contextRef="rc" decimals="2" id="ixv-187" unitRef="USD">1042963.85</ffd:TtlFeeAmt>
    <ffd:TtlPrevslyPdAmt contextRef="rc" decimals="2" id="ixv-188" unitRef="USD">0.00</ffd:TtlPrevslyPdAmt>
    <ffd:TtlOffsetAmt contextRef="rc" decimals="2" id="ixv-189" unitRef="USD">0.00</ffd:TtlOffsetAmt>
    <ffd:NetFeeAmt contextRef="rc" decimals="2" id="ixv-190" unitRef="USD">1042963.85</ffd:NetFeeAmt>
    <ffd:OfferingNote contextRef="offrl_1" id="ixv-191">Capitalized terms used below but not defined herein shall have the meanings assigned to such terms in the Business Combination Agreement, dated as of February 9, 2026, between Transocean Ltd. ("Transocean") and Valaris Limited ("Valaris").

(i)	Title of each class of securities to which transaction applies:

Common shares of Valaris, par value $0.01 per share ("Valaris Shares").

(ii)	Aggregate number of securities to which transaction applies:

As of the close of business on May 13, 2026, the maximum number of Valaris Shares to which this transaction applies is estimated to be 77,769,915, which consists of (a) 69,251,780 issued and outstanding Valaris Shares; (b) 3,047,334 Valaris Shares underlying time-based restricted stock units and performance-based restricted stock units that are outstanding or estimated to be issuable prior to the Effective Date and (c) 5,470,801 Valaris Shares estimated to be issuable after the Effective Date upon the exercise of Valaris Warrants.

(iii)	Per unit price of other underlying value of transaction computed pursuant to Rule 0-11 under the Securities Exchange Act of 1934, as amended (the "Exchange Act"):

Solely for the purpose of calculating the filing fee pursuant to Exchange Act Rule 0-11(c), the underlying value of the transaction was calculated based on the product of (A) 77,769,915 Valaris Shares, which consists of (i) 69,251,780 issued and outstanding Valaris Shares; (ii) 3,047,334 Valaris Shares underlying time-based restricted stock units and performance-based restricted stock units that are outstanding or estimated to be issuable prior to the Effective Date and (iii) 5,470,801 Valaris Shares estimated to be issuable after the Effective Date upon the exercise of Valaris Warrants) and (B) $97.11, the average of the high and low prices per Valaris Share as of May 12, 2026, as quoted on the New York Stock Exchange (such product, the "Maximum Aggregate Value").

Pursuant to Exchange Act Rule 0-11(c) and Section 14(g) of the Exchange Act, the filing fee equals the product of 0.0001381 multiplied by the Maximum Aggregate Value.</ffd:OfferingNote>
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