Contract Balances (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Revenue from Contract with Customer [Abstract]
Contract asset	$ 13.6		$ 13.6
Revenue recognized, recorded in deferred revenue as of prior period	$ 43.2	$ 34.2	$ 37.0	$ 31.5