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      contextRef="c20261019to20261019"
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      contextRef="c20261019to20261019"
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_CommonStockMember"
      id="Fact_d9cead2fca6f4000acea4f1d60dfb7fb">Voting Common Shares, par value $1.00 per share</dei:Security12bTitle>
    <dei:TradingSymbol
      contextRef="c20261019to20261019_StatementClassOfStockAxis_CommonStockMember"
      id="Fact_5567078e7af54ed190db93c10acddfd8">JEF</dei:TradingSymbol>
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_CommonStockMember"
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_Four850SeniorNotesDue2027Member"
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_Four850SeniorNotesDue2027Member"
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_Two750SeniorNotesDue2032Member"
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      contextRef="c20261019to20261019_StatementClassOfStockAxis_Six200SeniorNotesDue2034Member"
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