Revenue from Contracts with Customers - Accounts Receivable Reserve for Doubtful Accounts (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance as of beginning of fiscal year	$ 4.3	$ 4.6
Expense to increase the reserve	0.2	0.1
Write-off of uncollectible accounts	(0.3)	(0.3)
Balance as of period end	$ 4.2	$ 4.4