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GEOTHERMAL
12 Months Ended
Dec. 31, 2012
GEOTHERMAL [Abstract]  
GEOTHERMAL
G.                   GEOTHERMAL

During the year ended December 31, 2012, USE's minority interest investment in SST, a Denver, Colorado based private geothermal resource acquisition and development company, decreased. Due to not funding cash calls from SST during 2012, USE's ownership interest decreased from 22.4% to 19.54%.