v2.4.0.6

Acquisitions and divestments (Details) (USD $) In Millions, except Share data, unless otherwise specified		0 Months Ended			1 Months Ended			0 Months Ended		1 Months Ended			1 Months Ended			0 Months Ended
	Apr. 30, 2013	May 02, 2013 Canadian Hills	Jul. 31, 2012 Canadian Hills	Mar. 30, 2012 Canadian Hills	Dec. 31, 2012 Canadian Hills item	Mar. 31, 2013 Canadian Hills	Jan. 31, 2012 Canadian Hills MW	Apr. 12, 2013 Auburndale, Lake and Pasco	Jan. 30, 2013 Auburndale, Lake and Pasco	Apr. 30, 2013 Auburndale, Lake and Pasco	Apr. 30, 2013 Path 15	Mar. 31, 2013 Path 15	May 31, 2012 Primary Energy Recycling Corporation	Feb. 29, 2012 Primary Energy Recycling Corporation	Feb. 16, 2012 Primary Energy Recycling Corporation	Apr. 02, 2013 Gregory	Mar. 31, 2013 Gregory	Mar. 31, 2013 Delta-Person
Acquisition and divestments
Percentage acquired in entity				48.00%			51.00%
Percentage of ownership interest				99.00%											14.30%		17.10%	40.00%
Wind power project capacity (in MW)							300
Percentage of retained interest				1.00%
Project-level construction financing facility				$ 310.0								$ 137.2
Construction loan				290.0
Letter of credit facility	82.5			20.0
Letter of credit facility, term				5 years
Investment in equity			190
Tax equity investments received					225
Number of institutional tax equity investors by whom tax equity investments received					4
Own tax equity investment					44
Proceeds from sale of remaining tax equity ownership		42.1						92.0		25.0
Short-term debt					265	0
Entity's common membership interest to be purchased in equity method investee (in shares)														7,462,830.33
Expected proceeds from sale																33.7
Outstanding balance of senior credit facility								64.1
Price of entity's common membership interest in equity method investee														24.2
Management termination fee											4.0			6.0
Total price									140.0		56.0			30.2		272.8
Net cash proceeds from sale								117			52
Gain in equity in earnings of unconsolidated affiliates											$ 7.0		$ 0.6

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Represents the capacity of wind power project.

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Percentage of voting equity interests acquired in the business combination.

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