Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (d)(2)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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Stock-Based Compensation (Stock Options Exercisable) (Details) - Stock Options - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013	Jun. 30, 2014	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	$ 9.11	$ 7.37	$ 6.71	$ 7.37	$ 9.37
Amtech common stock per share price on January 30, 2015	$ 4.3
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Total Intrinsic Value (less than .1 million in 2013, less than .1 million in 2012, and 1.3 million in 2011)	$ 1.1	$ 1.3	$ 0.1
2.95-3.30
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	$ 2.96
3.80-7.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	5.69
7.01-7.14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.01
7.15-7.87
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.60
7.88-8.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.98
8.01-9.94
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	8.93
9.95-10.49
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	9.98
10.50-15.23
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	11.80
15.24-22.26
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	18.00
27.47-25.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	27.47
Minimum \| 2.95-3.30
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	2.95
Minimum \| 3.80-7.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	3.80
Minimum \| 7.01-7.14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.01
Minimum \| 7.15-7.87
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.15
Minimum \| 7.88-8.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.88
Minimum \| 8.01-9.94
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	8.01
Minimum \| 9.95-10.49
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	9.95
Minimum \| 10.50-15.23
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	10,500.00
Minimum \| 15.24-22.26
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	15.24
Minimum \| 27.47-25.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	27.47
Maximum \| 2.95-3.30
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	3.30
Maximum \| 3.80-7.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7
Maximum \| 7.01-7.14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.14
Maximum \| 7.15-7.87
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	7.87
Maximum \| 7.88-8.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	8.00
Maximum \| 8.01-9.94
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	9.94
Maximum \| 9.95-10.49
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	10.49
Maximum \| 10.50-15.23
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	15,230.00
Maximum \| 15.24-22.26
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	22.26
Maximum \| 27.47-25.00
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average Exercise Price	$ 25.00