Acquisitions - Pro Forma (Details) - BTU International, Inc (BTU) Merger - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Business Acquisition, Pro Forma Information [Abstract]
Revenue, net	$ 121,186	$ 111,531	$ 84,641
Net loss	$ (9,223)	$ (15,586)	$ (40,108)
Earnings per share available to Amtech stockholders:
Basic (in dollars per share)	$ (0.70)	$ (1.21)	$ (3.03)
Diluted (in dollars per share)	$ (0.70)	$ (1.21)	$ (3.03)

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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The pro forma diluted net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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