Goodwill and Other Assets Schedule of Intangible Assets (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	$ 1,053.3	$ 906.4
Accumulated amortization	(259.8)	(133.5)
Net carrying amount	793.5	772.9
Internally-developed software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	184.0	151.0
Accumulated amortization	(86.9)	(53.2)
Net carrying amount	97.1	97.8
Development costs non-software [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	53.9	48.4
Accumulated amortization	(30.8)	(9.7)
Net carrying amount	23.1	38.7
Customer relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	727.7	621.7
Accumulated amortization	(86.1)	(25.4)
Net carrying amount	641.6	596.3
Other intangibles [Member]
Finite-Lived Intangible Assets [Line Items]
Gross carrying amount	87.7	85.3
Accumulated amortization	(56.0)	(45.2)
Net carrying amount	$ 31.7	$ 40.1