Long-term Debt (Details 3) (ABL Revolver, USD $) In Millions, unless otherwise specified	6 Months Ended
	Mar. 31, 2012 Month	Sep. 30, 2011
Long-term debt
Maximum borrowing capacity	$ 70.0
Maximum borrowing capacity sublimit available for letters of credit	35.0
Maximum borrowing capacity available under the swingline facility	10.5
Current borrowing capacity	43.5
Line of credit facility, interest rate at period end (as a percent)	3.20%
Outstanding standby letters of credit		$ 16.1
Termination period prior to the earliest maturity date of long-term debt (in months)	3
Specified percentage under ABL Revolver	15.00%
Maximum
Long-term debt
Line of credit facility unused capacity commitment fee percentage	0.50%
Minimum
Long-term debt
Line of credit facility unused capacity commitment fee percentage	0.25%
Coverage ratio	1.0
LIBOR
Long-term debt
Percentage points added to the reference rate, one	2.25%
Percentage points added to the reference rate, two	2.50%
Percentage points added to the reference rate, three	2.75%
Base rate
Long-term debt
Percentage points added to the reference rate, one	1.00%
Percentage points added to the reference rate, two	1.25%
Percentage points added to the reference rate, three	1.50%
Federal funds rate
Long-term debt
Interest rate margin (as a percent)	0.50%
30-day LIBOR
Long-term debt
Interest rate margin (as a percent)	1.00%