Intangible Assets (Details) $ in Thousands	9 Months Ended		12 Months Ended
	Sep. 30, 2019 USD ($) a	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)
Finite-Lived Intangible Assets [Line Items]
Beginning balance	$ 158,706	$ 172,166	$ 172,166
Amortization	(10,095)	$ 10,100	(13,460)
Ending balance	$ 148,611		$ 158,706
Dimmit, La Salle And Webb Counties, Texas | Sanchez Energy
Finite-Lived Intangible Assets [Line Items]
Net acres | a	106,000
Customer Contracts
Finite-Lived Intangible Assets [Line Items]
Agreement term (in years)	15 years
Dedicated acreage | a	35,000
Useful life	15 years