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      <Label>Derivatives and Hedges (Policies) [Abstract]</Label>
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      <Label>NYSE Euronext adopted the Subtopic 65 in the Derivatives and Hedging Topic of the FASB Accounting Standards Codification on January 1, 2009</Label>
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   &lt;div align="left" style="font-size: 10pt; margin-top: 6pt"&gt;NYSE Euronext may use derivative instruments to hedge financial risks related to its financial
   position or risks that are otherwise incurred in the normal course of its operations. NYSE Euronext
   does not use derivative instruments for speculative purposes and enters into derivative instruments
   only with counterparties that meet high creditworthiness and rating standards. NYSE Euronext
   adopted Subtopic 65 in the Derivatives and Hedging Topic of the FASB Accounting Standards
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      <ElementDefenition>Describes an entity's accounting policies for its derivative instruments and hedging activities. Disclosure may include: (1) Each method used to account for derivative financial instruments and derivative commodity instruments ("derivatives"); (2) the types of derivatives accounted for under each method; (3) the criteria required to be met for each accounting method used, including a discussion of the criteria required to be met for hedge or deferral accounting and accrual or settlement accounting (for example: whether and how risk reduction, correlation, designation, and effectiveness tests are applied); (4) the accounting method used if the criteria specified for hedge accounting are not met; (5) the method used to account for termination of derivatives designated as hedges or derivatives used to affect directly or indirectly the terms, fair values, or cash flows of a designated item; (6) the method used to account for derivatives when the designated item matures, is sold, is extinguished, or is terminated. In addition, the method used to account for derivatives designated to an anticipated transaction, when the anticipated transaction is no longer likely to occur; and (7) where and when derivatives, and their related gains (losses) are reported in the statement of financial position, cash flows, and results of operations and (8) an accounting policy decision to offset fair value amounts with counterparties. An entity should also consider describing its embedded derivatives, and the method(s) used to determine the fair values of derivatives and any significant assumptions used in such valuations.</ElementDefenition>
      <ElementReferences>Reference 1: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name Statement of Financial Accounting Standard (FAS)
 -Number 133
 -Paragraph 44

Reference 2: http://www.xbrl.org/2003/role/presentationRef
 -Publisher SEC
 -Name Regulation S-X (SX)
 -Number 210
 -Section 08
 -Paragraph n
 -Article 4

Reference 3: http://www.xbrl.org/2003/role/presentationRef
 -Publisher FASB
 -Name FASB Interpretation (FIN)
 -Number 39
 -Paragraph 10

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