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Impairment of Inventory and Long-Lived Assets for Discontinued Operations - Additional Disclosures (Details)
3 Months Ended
Mar. 31, 2017
USD ($)
Mar. 31, 2016
USD ($)
rig
segment
Dec. 31, 2015
rig
Property, Plant and Equipment [Line Items]      
Decrease in crude oil prices   21.00%  
Number of segments tested for goodwill (segment) | segment   2  
Impairments of goodwill | $ $ 0 $ 0  
UNITED STATES      
Property, Plant and Equipment [Line Items]      
Number of drilling rigs (rig) | rig   450 698
Decrease in number of drilling rigs   35.50%