Segment Data and Related Information (Schedule of Depreciation, Amortization, and Accretion Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	$ 2,044	$ 2,377	$ 4,062	$ 5,152
Fiber Optics
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	1,384	1,271	2,666	2,926
Photovoltaics
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	$ 660	$ 1,106	$ 1,396	$ 2,226