Long-Term Debt (Details Textuals) (USD $) In Millions, unless otherwise specified	3 Months Ended	60 Months Ended	3 Months Ended
	Jun. 30, 2011	Sep. 01, 2016 years	Jun. 30, 2011 Senior Notes2 [Member]	Sep. 30, 2011 Tax-Exempt Revenue Bonds4 [Member]
Debt Instrument [Line Items]
interest rate is reset every three months	3
Debt Instrument, Basis Spread on Variable Rate	7000.00%
Time Period Bonds were Remarketed for		5
Extinguishment of Debt, Amount	$ 991		$ 600	$ 140