Commitments And Contingencies (Details) (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Cash performance unit awards
Commitments and Contingencies
Performance period, years				P5Y
Amount of free cash flow performance goals				$ 850.0
Amount of free cash flow achieved	232.9
Amount of free cash flow expenses accrued	2.6
Amount of free cash flow expenses accrued and unpaid	1.8
Maximum payout	27.6
Percentage of performance units vested		50.00%	50.00%
Average stock price period (in days)			P60D
Expense related solely to increase in average stock price			0.2
Average closing stock price (in dollars per share)			$ 2.40
Maximum payout under stock price method	0.8
SARs
Commitments and Contingencies
Percentage of stock price on grant date	135.00%
Average stock price period (in days)	P60D
Grants approved by committee to employees for cash settled stock appreciation rights (in shares)	1.0		0.4
Amount accrued for awards	0.1
Amount accrued for awards if stock price below grant date price	$ 0
Grant-date stock price (in dollars per share)	$ 1.85		$ 3.81
Threshhold stock price at which SARS will vest (in dollars per share)	$ 2.50