Other Information (Details) - USD ($)	Jun. 30, 2018	Dec. 31, 2017
Other Current Assets:
Natural gas and NGLs inventory	$ 60,800,000	$ 30,100,000
Secured term loan receivable from contract restructuring, net of discount of $1.6	17,900,000	0
Secured term loan receivable, discount	1,600,000	0
Prepaid expenses and other	20,400,000	11,100,000
Natural gas and NGLs inventory, prepaid expenses, and other	99,100,000	41,200,000
Other Current Liabilities:
Accrued interest	36,600,000	35,600,000
Accrued wages and benefits, including taxes	18,000,000	30,400,000
Accrued ad valorem taxes	25,900,000	27,800,000
Capital expenditure accruals	41,800,000	48,800,000
Onerous performance obligations	17,900,000	15,200,000
Other	66,200,000	65,100,000
Other current liabilities	$ 206,400,000	$ 222,900,000