Commitments and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Other Commitments [Line Items]
Remaining principal balance	$ 45.5		$ 42.4
Payment to ESCO for debt repayment and repurchase of shares	6.2
Gain on debt retirement	2.1	$ 0.0
Repurchase of Class A Common Stock	3.1
ESCO Notes Payable due February 2019
Other Commitments [Line Items]
Remaining principal balance	0.0		$ 5.8	$ 5.8
Payment for retirement of debt	3.8
Gain on debt retirement	2.1
Class A Common Stock
Other Commitments [Line Items]
Repurchase of Class A Common Stock	$ 2.4