Intangible Assets (Schedule of Intangible Assets Subject to Amortization) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Sep. 30, 2012
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	$ 30,465	$ 30,534
Accumulated Amortization	(18,853)	(17,217)
Net Carrying Value	11,612	13,317
Supply Agreement
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	17,580	17,580
Accumulated Amortization	(8,397)	(7,225)
Net Carrying Value	9,183	10,355
Purchased Technology
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	11,749	11,818
Accumulated Amortization	(9,489)	(9,121)
Net Carrying Value	2,260	2,697
Trade Names
Finite Lived Intangible Assets [Line Items]
Gross Carrying Value	1,136	1,136
Accumulated Amortization	(967)	(871)
Net Carrying Value	$ 169	$ 265