Segment Data and Related Information - Schedule of Depreciation, Amortization, and Accretion Expense (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	$ 8,518	$ 8,688	$ 9,420
Fiber Optics
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	5,986	5,737	5,246
Photovoltaics
Segment Reporting Information [Line Items]
Depreciation, amortization, and accretion expense	$ 2,532	$ 2,951	$ 4,174

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

Name:	us-gaap_DepreciationDepletionAndAmortization
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration