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Summary of Significant Accounting Policies - Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Deferred revenue contract liability	$ 70.3		$ 70.3		$ 30.6
Performance obligation timing			We expect to recognize substantially all of these amounts in revenues within approximately 12 months.
Deferred revenue recognized	$ 4.6		$ 29.6
Maximum
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Derivative term of contract			1 year
Sales Revenue
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Consolidated revenues, net (percent)	100.00%	100.00%	100.00%	100.00%
Contracts with customers \| Sales Revenue
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Consolidated revenues, net (percent)	80.00%		80.00%