Intangible Assets (Schedule Of Intangible Assets Subject To Amortization) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Sep. 30, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 30,514	$ 30,534
Accumulated Amortization	(17,627)	(17,217)
Net Carrying Value	12,887	13,317
Supply Agreement [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	17,580	17,580
Accumulated Amortization	(7,518)	(7,225)
Net Carrying Value	10,062	10,355
Purchased Technology [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	11,798	11,818
Accumulated Amortization	(9,214)	(9,121)
Net Carrying Value	2,584	2,697
Trade Name [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Value	1,136	1,136
Accumulated Amortization	(895)	(871)
Net Carrying Value	$ 241	$ 265