Derivative Instruments Narrative (Details) In Millions, unless otherwise specified	3 Months Ended			7 Months Ended
	Dec. 31, 2012 USD ($)	Mar. 31, 2012 USD ($)	Mar. 28, 2012 CAD	Dec. 31, 2012 Interest Expense USD ($)	Dec. 31, 2012 Derivative Liability USD ($)
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value of put option					$ 7.8
Unrealized gain on change in put option fair value				(1.2)
Notional amount of derivatives			870.0
Realized loss on settlement of derivative forward contracts	$ 37.6	$ 6.7