Revenue From Contracts With Customers - Contract Liabilities (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Contract with customer, liability	$ 53.7	$ 63.1
Contract with customer, revenue recognized	$ 6.7	$ 51.2	$ 53.7