Goodwill and Intangible Assets - Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	$ 458.5		$ 473.6
Accumulated Amortization, intangible assets subject to amortization	(245.1)		(244.5)
Net Carrying Amount, intangible assets subject to amortization	213.4		229.1
Amortization expense related to intangible assets subject to amortization	8.9	$ 8.7
Technology
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	299.0		309.8
Accumulated Amortization, intangible assets subject to amortization	(192.3)		(194.6)
Net Carrying Amount, intangible assets subject to amortization	106.7		115.2
Customer relationships
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	144.4		148.3
Accumulated Amortization, intangible assets subject to amortization	(48.0)		(45.4)
Net Carrying Amount, intangible assets subject to amortization	96.4		102.9
Trade name
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	14.8		15.2
Accumulated Amortization, intangible assets subject to amortization	(4.7)		(4.4)
Net Carrying Amount, intangible assets subject to amortization	10.1		10.8
Other
Intangible assets
Gross Carrying Amount, intangible assets subject to amortization	0.3		0.3
Accumulated Amortization, intangible assets subject to amortization	(0.1)		(0.1)
Net Carrying Amount, intangible assets subject to amortization	$ 0.2		$ 0.2