Intangible Assets and Goodwill (Schedule of Goodwil)l (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Goodwill [Roll Forward]
Balance at the beginning of the period	$ 4,108.3us-gaap_Goodwill	$ 1,183.1us-gaap_Goodwill
Acquisitions		2,956.1us-gaap_GoodwillAcquiredDuringPeriod
Foreign currency adjustments	(77.3)us-gaap_GoodwillTranslationAdjustments	(30.9)us-gaap_GoodwillTranslationAdjustments
Balance at the end of the period	4,031.0us-gaap_Goodwill	4,108.3us-gaap_Goodwill
Interactive
Goodwill [Roll Forward]
Balance at the beginning of the period	3,499.7	612.7
Acquisitions		2,902.8
Foreign currency adjustments	(65.0)	(15.8)
Balance at the end of the period	3,434.7	3,499.7
Lottery
Goodwill [Roll Forward]
Balance at the beginning of the period	498.8	513.9
Acquisitions		0
Foreign currency adjustments	(12.3)	(15.1)
Balance at the end of the period	486.5	498.8
Interactive (1)
Goodwill [Roll Forward]
Balance at the beginning of the period	109.8	56.5
Acquisitions		53.3
Foreign currency adjustments	0	0
Balance at the end of the period	$ 109.8	$ 109.8

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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