Supplemental Disclosures (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Allowance for Doubtful Accounts
Beginning balance	$ 1.5	$ 1.7	$ 1.0
Bad debt expense	1.0	0.4	1.2
Recoveries	0.0	(0.3)	(0.2)
Write-offs and discounts	(1.4)	(0.3)	(0.3)
Ending balance	1.1	1.5	1.7
Interest paid	31.4	29.1	24.0
Income taxes paid	14.8	20.8	23.2
Capital spending in accounts payable and accrued liabilities	$ 5.2	$ 5.9	$ 5.0

Amount of allowance for credit loss on accounts receivable.

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