Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accrued Liabilities
Accrued capital expenditures	$ 35,608	$ 50,022
Aaccrued operating expenses	14,582	26,896
Accrued interest expense	10,613	82
Accrued ad valorem taxes		7,195
Other	838	1,190
Accrued liabilities	$ 61,641	$ 85,385