XML 67 R34.htm IDEA: XBRL DOCUMENT v2.4.0.8
Inventory - Schedule of Inventory (Detail) (USD $)
In Thousands, unless otherwise specified
Jun. 30, 2014
Dec. 31, 2013
Inventory Disclosure [Abstract]    
Equipment and materials $ 7,222 $ 11,669
Crude oil inventory 10,414 8,983
Total inventory $ 17,636 $ 20,652