Goodwill and Intangible Assets - Intangible Assets Subject to Amortization (Details) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 3,587.1	$ 3,295.0
Accumulated Amortization	(835.6)	(438.7)
Net Book Value	2,751.5	2,856.3
Customer Lists
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	1,303.3	1,245.9
Accumulated Amortization	(263.5)	(174.5)
Net Book Value	1,039.8	1,071.4
Developed technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,250.7	2,022.1
Accumulated Amortization	(557.0)	(254.9)
Net Book Value	1,693.7	1,767.2
Trade names
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	30.3	25.1
Accumulated Amortization	(13.8)	(8.2)
Net Book Value	16.5	16.9
Non-compete agreement
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2.8	1.9
Accumulated Amortization	(1.3)	(1.1)
Net Book Value	$ 1.5	$ 0.8