Acxiom Acquisition Pro Forma (Details) - Acxiom - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Business Acquisition, Pro Forma Revenue	$ 10,230.4	$ 9,736.1
Business Acquisition, Pro Forma Net Income (Loss)	$ 642.2	$ 519.2
After-tax nonrecurring transaction-related charges		27.6

Description of the pro forma information, nature of adjustments made to historical information to arrive at pro forma amounts, amounts excluded from pro forma information, any material-nonrecurring items included in the pro forma information and limitations of pro forma disclosures.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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