Subsequent Event (Details) (USD $)	Jun. 30, 2012	Aug. 07, 2012 New Credit Agreement [Member]
Subsequent Event [Line Items]
NewDebtAvailability		$ 1,000,000,000
NewDebtRefinancedAmount		$ 272,100,000
Line Of Credit Average Interest Rate	1.26%	1.50%
Ratio of Indebtedness to Net Capital	3.5	3.5
Fixed Charge Coverage Ratio	1.25	1.25
Percentage Of Indebtedness To Net Capital	65.00%	65.00%