Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 2,841	$ (1,381)	$ 767	$ (7,808)
Foreign currency translation adjustment	740	(299)	118	(217)
Comprehensive income (loss)	3,581	(1,680)	885	(8,025)
Comprehensive loss attributable to noncontrolling interest	302	197	969	1,084
Comprehensive income (loss) attributable to Amtech Systems, Inc.	$ 3,883	$ (1,483)	$ 1,854	$ (6,941)

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.

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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.

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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.

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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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