Restricted Cash And Investments (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Apr. 02, 2011	Dec. 31, 2011
Restricted Cash and Cash Equivalents Items [Line Items]
Qualified expenditures for construction of facility	$ 0	$ 21,900,000
Restricted investments	474,200,000		514,300,000
Nov. 30, 2010 30-Year Variable Rate Gulf Opportunity Zone Bonds [Member]
Restricted Cash and Cash Equivalents Items [Line Items]
Debt instrument face amount	$ 600,000,000
Term of variable rate bonds, years	30