Consolidated Statements of Comprehensive Income Consolidated Statements of Comprehensive Income (USD $) In Thousands, unless otherwise specified	12 Months Ended
Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Statement of Comprehensive Income [Abstract]
Net loss	$ (14,289)	$ (21,707)	$ (27,598)
Foreign currency translation adjustment	(1,202)	2,225	(4,853)
Comprehensive loss	(15,491)	(19,482)	(32,451)
Comprehensive loss attributable to noncontrolling interest	1,210	1,674	4,681
Comprehensive loss attributable to Amtech Systems, Inc.	$ (14,281)	$ (17,808)	$ (27,770)

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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