Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Sep. 30, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 30,457	$ 30,534
Accumulated Amortization	(18,461)	(17,217)
Net Carrying Value	11,996	13,317
Supply Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	17,580	17,580
Accumulated Amortization	(8,104)	(7,225)
Net Carrying Value	9,476	10,355
Purchased Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	11,741	11,818
Accumulated Amortization	(9,388)	(9,121)
Net Carrying Value	2,353	2,697
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	1,136	1,136
Accumulated Amortization	(969)	(871)
Net Carrying Value	$ 167	$ 265