Condensed Consolidated Statements Of Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Statement of Comprehensive Income [Abstract]
Net loss	$ (5,153)	$ (12,666)	$ (10,639)	$ (19,555)
Foreign currency translation adjustment	(335)	676	406	599
Comprehensive loss	(5,488)	(11,990)	(10,233)	(18,956)
Comprehensive (income) loss attributable to noncontrolling interest	(80)	603	844	1,224
Comprehensive loss attributable to Amtech Systems, Inc.	$ (5,568)	$ (11,387)	$ (9,389)	$ (17,732)

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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-Name Accounting Standards Codification

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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, attributable to noncontrolling interests. 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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