Business, Product and Geographical Area Information and Concentration of Risk - Schedule of net sales, income taxes paid, and long-lived assets, by geographical area (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers, Income Taxes Paid, and Long-Lived Assets
Net sales	$ 368.7	$ 374.9	$ 375.3	$ 395.2	$ 389.4	$ 393.1	$ 415.4	$ 388.0	$ 1,514.1	$ 1,585.9	$ 1,397.5
Income taxes paid									5.5	3.6	1.3
Long-lived assets	622.0				611.8				622.0	611.8	571.4
United States
Revenues from External Customers, Income Taxes Paid, and Long-Lived Assets
Net sales									1,461.4	1,509.6	1,337.3
Income taxes paid									3.5	1.6	1.2
Long-lived assets	592.9				581.7				592.9	581.7	541.2
Non-US [Member]
Revenues from External Customers, Income Taxes Paid, and Long-Lived Assets
Income taxes paid									2.0	2.0	0.1
Canada
Revenues from External Customers, Income Taxes Paid, and Long-Lived Assets
Net sales									52.7	76.3	60.2
Long-lived assets	$ 29.1				$ 30.1				$ 29.1	$ 30.1	$ 30.2