Quarterly report pursuant to Section 13 or 15(d)

Assets Held for Sale - Additional Information (Detail)

v2.4.0.8
Assets Held for Sale - Additional Information (Detail) (USD $)
 3 Months Ended 3 Months Ended 12 Months Ended
Mar. 31, 2014
Dec. 31, 2013
Mar. 31, 2014
Cheviot Project [Member]
Dec. 31, 2012
Cheviot Project [Member]
Mar. 31, 2013
Cheviot Project [Member]
Long Lived Assets Held-for-sale [Line Items]          
Contract receivables monthly payments     $ 200,000    
Contract receivables monthly payments end date     Feb. 28, 2013    
Amount billed on customers       56,800,000  
Contracts receivable 92,504,000 98,579,000   31,300,000 30,900,000
Provision for loss on contract receivable       14,500,000  
Fair value of assets held for sale $ 13,500,000   $ 13,500,000    
Percentage of fair value of assets held for sale under sales assistance agreement 50.00%