Accrued Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Accrued Liabilities Detail [Table]
Compensation and employee benefits	$ 12,681	$ 27,276
Oil and gas producing liabilities	9,335	12,723
Unearned income	6,782	6,988
Deferred tax liability		11,857	$ 13,695
Other accrued liabilities	14,981	20,288
Accrued liabilities	$ 55,636	$ 80,970