Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	$ 413.0		$ 403.1
Accumulated Amortization, intangible assets subject to amortization	(193.7)		(184.4)
Net Carrying Amount, intangible assets subject to amortization	219.3		218.7
Amortization expense related to intangible assets subject to amortization	10.1	$ 6.8
Existing technology and related patents
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	277.6		272.6
Accumulated Amortization, intangible assets subject to amortization	(164.8)		(160.5)
Net Carrying Amount, intangible assets subject to amortization	112.8		112.1
Customer relationships
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	116.2		112.0
Accumulated Amortization, intangible assets subject to amortization	(20.8)		(18.1)
Net Carrying Amount, intangible assets subject to amortization	95.4		93.9
Non compete contracts
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	1.8		1.8
Accumulated Amortization, intangible assets subject to amortization	(1.8)		(1.8)
Trade names
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	11.9		11.6
Accumulated Amortization, intangible assets subject to amortization	(1.9)		(1.6)
Net Carrying Amount, intangible assets subject to amortization	10.0		10.0
Other
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	5.5		5.1
Accumulated Amortization, intangible assets subject to amortization	(4.4)		(2.4)
Net Carrying Amount, intangible assets subject to amortization	$ 1.1		$ 2.7