XML 37 R15.htm IDEA: XBRL DOCUMENT

Financial Instruments	3 Months Ended
Financial Instruments	Mar. 31, 2013
Financial Instruments [Abstract]
Financial Instruments	6. Financial Instruments Financial instruments on the consolidated balance sheets that approximate fair value include: cash and cash equivalents, receivables, investments carried at fair value, payables, accrued liabilities, interest rate swaps and variable rate long-term debt.