Goodwill and Identifiable Intangible Assets, net - Summary of Identifiable Intangible Assets, net (Details) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 180.5	$ 172.0
Accumulated Amortization	(103.8)	(97.3)
Net	76.7	74.7
Total identifiable intangible assets, net
Gross Carrying Value	189.4	180.9
Net	85.6	83.6
Trademarks and tradenames with indefinite lives
Indefinite-lived Intangible Assets [Line Items]
Trademarks and tradenames with indefinite lives	8.9	8.9
Customer relationships
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	54.7	59.7
Accumulated Amortization	(20.7)	(19.7)
Net	34.0	40.0
Trademarks and tradenames with indefinite lives
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	11.2	11.6
Accumulated Amortization	(0.8)	(0.5)
Net	10.4	11.1
Capitalized software
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	58.6	50.6
Accumulated Amortization	(44.3)	(40.0)
Net	14.3	10.6
Technology
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	42.5	39.2
Accumulated Amortization	(28.1)	(27.5)
Net	14.4	11.7
Contracts
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	13.5	10.9
Accumulated Amortization	(9.9)	(9.6)
Net	$ 3.6	$ 1.3