Revenue from Contracts with Customers - Revenue Disaggregated by Service Offering (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenue	$ 123.4	$ 79.1	$ 336.5	$ 202.2
Subscription
Disaggregation of Revenue [Line Items]
Total revenue	122.4	78.0	333.3	199.2
Usage-based
Disaggregation of Revenue [Line Items]
Total revenue	$ 1.0	$ 1.1	$ 3.2	$ 3.0