v3.3.1.900

Goodwill (Details) GWh in Thousands, $ in Millions	3 Months Ended		12 Months Ended
	Sep. 30, 2014 USD ($)	Jun. 30, 2014 USD ($)	Dec. 31, 2015 USD ($) GWh item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Goodwill
Impairment of goodwill	$ 91.8		$ 51.2
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance			197.2	$ 296.3
Impairment of goodwill	(91.8)		(51.2)
Impairment of goodwill including Rollcast				(97.0)
Translation Adjustments			(11.5)	(2.1)
Goodwill, Ending Balance			134.5	197.2	$ 296.3
Amount by which fair value exceeds carrying value			$ 118.0
Fair value in excess carrying value (as a percent)			37.00%
Number of asset groups tested | item			5
Long lived asset impairment charge			$ 76.6	9.6
Impairment charges			127.8	106.6	39.7
Morris
Changes in the carrying amount of goodwill
Goodwill, Ending Balance			3.3
Nipigon
Changes in the carrying amount of goodwill
Goodwill, Ending Balance			3.6
Mamquam
Changes in the carrying amount of goodwill
Goodwill, Ending Balance			64.1
Curtis Palmer
Goodwill
Impairment of goodwill			$ 13.7
Quantity triggering agreement expiration | GWh			10
Expected period of expiration before specified date (in years)			2 years
Changes in the carrying amount of goodwill
Impairment of goodwill			$ (13.7)
Williams Lake
Goodwill
Impairment of goodwill			35.6
Changes in the carrying amount of goodwill
Impairment of goodwill			(35.6)
Long lived asset impairment charge			74.1
Calstock
Goodwill
Impairment of goodwill			1.9
Changes in the carrying amount of goodwill
Impairment of goodwill			(1.9)
Long lived asset impairment charge			2.5
East U.S.
Goodwill
Impairment of goodwill			13.7
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance			61.5	79.4
Impairment of goodwill			(13.7)
Impairment of goodwill including Rollcast				(17.9)
Goodwill, Ending Balance			47.8	61.5	79.4
East U.S. | Kenilworth
Goodwill
Impairment of goodwill	17.9
Changes in the carrying amount of goodwill
Impairment of goodwill	(17.9)
West U.S.
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance				50.3
Impairment of goodwill including Rollcast				(50.3)
Goodwill, Ending Balance					50.3
West U.S. | Manchief
Goodwill
Impairment of goodwill	50.2
Changes in the carrying amount of goodwill
Impairment of goodwill	(50.2)
Canada Segment [Member]
Goodwill
Impairment of goodwill			37.5
Changes in the carrying amount of goodwill
Goodwill, Beginning Balance			135.7	166.6
Impairment of goodwill			(37.5)
Impairment of goodwill including Rollcast				(28.8)
Translation Adjustments			(11.5)	(2.1)
Goodwill, Ending Balance			86.7	$ 135.7	$ 166.6
Canada Segment [Member] | Williams Lake
Goodwill
Impairment of goodwill	23.7
Changes in the carrying amount of goodwill
Impairment of goodwill	$ (23.7)
Canada Segment [Member] | Tunis Inc [Member]
Goodwill
Impairment of goodwill		$ 5.2
Changes in the carrying amount of goodwill
Impairment of goodwill		(5.2)
Long lived asset impairment charge		$ 9.6
Impairment charges			$ 14.8

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