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TRADE ACCOUNTS RECEIVABLE
12 Months Ended
Dec. 31, 2012
Receivables [Abstract]  
TRADE ACCOUNTS RECEIVABLE
14.
TRADE ACCOUNTS RECEIVABLE

Trade accounts receivable are presented net of allowances for doubtful accounts.  The provision for doubtful debts was $nil and $0.6 million for the years ended December 31, 2012 and 2011, respectively.