Income Taxes (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Related Party Transaction [Line Items]
Short-term deferred tax liability	$ 2,508		$ 5,937
Income tax rate	39.50%	15.50%
NuDevco Retail Holdings and NuDevco Retail
Related Party Transaction [Line Items]
Net deferred tax asset	$ 15,600
NuDevco Retail Holdings and NuDevco Retail | Tax Receivable Agreement
Related Party Transaction [Line Items]
Deferred tax liabilities	28,600
Deferred tax assets	7,200
NuDevco Retail Holdings and NuDevco Retail | Tax Receivable Agreement | Taxes Payable, Current, Related Parties
Related Party Transaction [Line Items]
Deferred tax liabilities	2,500		$ 5,900
Short-term deferred tax liability	$ 2,500