Segment Data and Related Information (Schedule of Stock-based Compensation Expense) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Segment Reporting Information [Line Items]
Stock-based compensation expense	$ 1,180	$ 1,152	$ 3,419	$ 3,285
Fiber Optics
Segment Reporting Information [Line Items]
Stock-based compensation expense	792	686	2,221	2,114
Photovoltaics
Segment Reporting Information [Line Items]
Stock-based compensation expense	$ 388	$ 466	$ 1,198	$ 1,171