Number of Former Employees Named as Defendants

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Number of Shareholders Commencing Punitive Derivative Action

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Amount of cash outflow to a noncontrolling interest. Includes, but not limited to, reduction of noncontrolling interest ownership. Excludes dividends paid to the noncontrolling interest.

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-Publisher FASB
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Commitments and Contingencies (Details) $ in Millions	3 Months Ended
Commitments and Contingencies (Details) $ in Millions	Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)	Jan. 31, 2016 employee	Aug. 31, 2015 shareholder
Loss Contingencies [Line Items]
Contribution to noncontrolling interest	$ 50	$ 24
Shareholder Derivative Action
Loss Contingencies [Line Items]
Number of shareholders commencing punitive derivative action \| shareholder				2
Affiliated Entity
Loss Contingencies [Line Items]
Contribution to noncontrolling interest	20
CME Group \| S&P DJ Indices
Loss Contingencies [Line Items]
Revenues earned under license agreement	$ 31
Noncontrolling interest ownership by noncontrolling owners (as a percent)	27.00%
S&P Global Ratings \| Shareholder Derivative Action
Loss Contingencies [Line Items]
Number of former employees named as defendants \| employee			9