Schedule of Intangible Assets by Reporting Segment (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Sep. 30, 2011
Balance:
Intangible assets, gross	$ 22,907	$ 24,359
Intangible assets, accumulated amortization	(19,162)	(18,493)
Intangible assets, net	3,745	5,866
Estimated Future Amortization Expense
Three months ended September 30, 2012	317
Fiscal year ended September 30, 2013	1,269
Fiscal year ended September 30, 2014	1,017
Fiscal year ended September 30, 2015	555
Fiscal year ended September 30, 2016	555
Thereafter	32
Intangible assets, net	3,745	5,866
Fiber Optics
Balance:
Intangible assets, gross	20,935	22,080
Intangible assets, accumulated amortization	(17,621)	(17,198)
Intangible assets, net	3,314	4,882
Estimated Future Amortization Expense
Intangible assets, net	3,314	4,882
Core Technology | Fiber Optics
Balance:
Intangible assets, gross	12,727	13,872
Intangible assets, accumulated amortization	(10,982)	(10,862)
Intangible assets, net	1,745	3,010
Estimated Future Amortization Expense
Intangible assets, net	1,745	3,010
Customer Relations | Fiber Optics
Balance:
Intangible assets, gross	3,511	3,511
Intangible assets, accumulated amortization	(2,287)	(2,071)
Intangible assets, net	1,224	1,440
Estimated Future Amortization Expense
Intangible assets, net	1,224	1,440
Patents | Fiber Optics
Balance:
Intangible assets, gross	4,697	4,697
Intangible assets, accumulated amortization	(4,352)	(4,265)
Intangible assets, net	345	432
Estimated Future Amortization Expense
Intangible assets, net	345	432
Patents | Photovoltaics
Balance:
Intangible assets, gross	1,972	2,279
Intangible assets, accumulated amortization	(1,541)	(1,295)
Intangible assets, net	431	984
Estimated Future Amortization Expense
Intangible assets, net	$ 431	$ 984