Accounts Payable and Accrued Liabilities (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Payables and Accruals [Abstract]
Accounts payable	$ 202,467	$ 238,758
Revenues payable	109,054	145,816
Accrued capital expenditures	29,926	61,950
Accrued interest	43,441	36,295
Accrued severance	20,708	28,803
Total accounts payable and accrued liabilities	$ 405,596	$ 511,622