Income Taxes - Reconciliation of the Statutory Rate (Details)	3 Months Ended		9 Months Ended		12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Sep. 30, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reconciliation of the statutory tax rate
Financial Designation, Predecessor and Successor [Fixed List]	Successor	Successor	Successor	Predecessor	Successor	Successor	Predecessor
Statutory U.S. federal income tax rate		21.00%		21.00%	21.00%		35.00%
State and local income taxes, net of federal income tax benefit		4.70%		5.10%	3.90%		2.80%
Foreign tax rate differential		3.70%		2.50%	(1.10%)		3.10%
Tax Cuts & Jobs Act Provisional Tax Charge							0.022
LLC flow-through structure		(19.00%)		(20.20%)			(36.30%)
Non-Controlling Interest					(7.20%)
Tax Receivable Agreement adjustment					(3.10%)
Rate Change					10.20%
Other					(0.50%)
Effective tax rate		10.40%		8.40%	23.20%		6.80%