Property, Equipment, and Leasehold Improvements, net (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended			3 Months Ended	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012 Operating expenses	Sep. 30, 2012 Minimum	Sep. 30, 2012 Maximum
Property, Plant and Equipment [Line Items]
Impairment for certain assets				$ 1.2
Cancellation notice period					2 months	3 months
Rental income	1.3	1.4	1.1
Depreciation	$ 0.1	$ 0.1	$ 0.1