Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Accrued Liabilities
Capital expenditures	$ 105,706	$ 113,237
Gathering, compression, processing, and transportation expenses	134,153	148,032
Marketing expenses	52,612	67,082
Interest expense, net	30,834	43,444
Other	77,545	93,275
Total accrued liabilities	$ 400,850	$ 465,070