Goodwill and Other Intangible Assets - Gross carrying amount and accumulated amortization of the company's intangible assets other than goodwill (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Intangible asset balances by major asset class
Intangible assets, gross (excluding goodwill)	$ 151.5	$ 153.5
Finite-lived intangible assets, amortization amount	(36.6)	(37.2)
Intangible assets, book value	114.9	116.3
Customer Relationships
Intangible asset balances by major asset class
Finite-lived intangible assets, carrying amount	9.7	10.0
Finite-lived intangible assets, amortization amount	(8.2)	(8.5)
Finite-lived intangible assets, book value	1.5	1.5
Patents
Intangible asset balances by major asset class
Finite-lived intangible assets, carrying amount	29.2	29.5
Finite-lived intangible assets, amortization amount	(28.4)	(28.7)
Finite-lived intangible assets, book value	0.8	0.8
Distribution Network
Intangible asset balances by major asset class
Finite-lived intangible assets, carrying amount	18.4	18.7
Finite-lived intangible assets, book value	18.4	18.7
Trademarks and Tradenames
Intangible asset balances by major asset class
Indefinite-lived intangible assets, book value	$ 94.2	$ 95.3