Accounts Receivable (Allowance for Doubtful Accounts) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at beginning of period		$ 3,332	$ 8,399	$ 7,125
Provision adjustment - expense, net of recoveries		(53)	30	2,238
Reclass of amount to a long-term receivables account	5,300	0	(5,253)	0
Impact from foreign exchange translation adjustment		0	181	103
Write-offs - deductions against receivables		0	25	1,067
Balance at end of period		$ 3,279	$ 3,332	$ 8,399