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Impairment of Inventory and Long-Lived Assets - Additional Disclosures (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2016
USD ($)
Mar. 31, 2016
USD ($)
segment
Jun. 30, 2015
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2015
USD ($)
Apr. 01, 2016
rig
Dec. 31, 2015
rig
Property, Plant and Equipment [Line Items]              
Decrease in crude oil prices (percent)   21.00%          
Number of segments tested for goodwill (segment) | segment   2          
Impairments of goodwill | $ $ 0 $ 0 $ 0 $ 0 $ 0    
UNITED STATES              
Property, Plant and Equipment [Line Items]              
Number of drilling rigs (rig) | rig           450 698
Decrease in number of drilling rigs (percent)           35.50%