v2.4.0.6

Segment and geographic information (Details 3) (Revenues, net, Consolidated revenue)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Ontario Electricity Financial Corp (OEFC)
Consolidated revenue concentration
Percentage of consolidated revenue	36.00%	40.30%
BC Hydro
Consolidated revenue concentration
Percentage of consolidated revenue	12.10%	12.90%

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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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-Publisher FASB

-Name Accounting Standards Codification

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-Name Accounting Standards Codification

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