Significant transactions - IMG Acquisition - Supplemental Pro Forma Information (Details) - IMG - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Supplemental Pro Forma Information
Total revenues	$ 1,176.8	$ 1,096.0
Net income	$ (173.2)	$ (4.6)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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-Publisher FASB
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