Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	1 Months Ended		3 Months Ended
	Jul. 05, 2011	May 23, 2012	Jan. 26, 2011	Jun. 30, 2013	Mar. 31, 2013
Site Contingency [Line Items]
Estimated cost, minimum			$ 7.9
Estimated cost, maximum			10.5
Estimated cost	9.5
Payments		1.75		1.10
Additional increase during period				1.75	0.75
Accrual amount				5.6
Loss Exposure in Excess of Accrual, Best Estimate				$ 1.0