v2.4.0.6

Summary of significant accounting policies (Tables)

12 Months Ended

Dec. 31, 2012

Summary of significant accounting policies

Summary of derivative financial instruments that are not designated as hedges for accounting purposes and the accounting treatment in the consolidated statements of operations of the changes in fair value and cash settlements of such derivative financial instrument

Derivative financial instrument		Classification of changes in fair value		Classification of cash settlements
Natural gas swaps		Changes in fair value of derivative instrument		Fuel expense
Gas purchase agreements		Changes in fair value of derivative instrument		Fuel expense
Interest rate swaps		Changes in fair value of derivative instrument		Interest expense
Foreign currency forward contract		Foreign exchange (gain) loss		Foreign exchange loss (gain)

X

- Definition

Tabular disclosure for other derivative instruments that are not designated as hedging instruments of (a) the location and amount of gains and losses reported in the statement of financial performance and (b) the location and fair value amounts of the instruments reported in the statement of financial position.

+ References

No definition available.

+ Details

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X

- Details

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