Detail of Certain Balance Sheet Accounts (Details) - EnerTech [Member]	12 Months Ended
Sep. 30, 2016
Schedule of Equity Cost Investments [Line Items]
Cost Method Investments Additional Information	we held an investment in EnerTech Capital Partners II L.P. (“EnerTech), a private investment fund
Equity Method Investment, Ownership Percentage	2.21%

This serves as a place to record data that is not specified elsewhere in the taxonomy but is useful for readers of the financial statements as it relates to the details of cost method investments.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 325
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6872867&loc=d3e40691-111596

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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