Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 8,086	$ (8,550)	$ (6,717)
Foreign currency translation adjustment	423	(199)	(3,010)
Comprehensive income (loss)	8,509	(8,749)	(9,727)
Comprehensive (income) loss attributable to non-controlling interest	969	1,531	(920)
Comprehensive income (loss) attributable to Amtech Systems, Inc.	$ 9,478	$ (7,218)	$ (10,647)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 45
-Paragraph 5
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income. Excludes changes in equity resulting from investments by owners and distributions to owners.

+ References

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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