Basis of Presentation - Goodwill (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended
Mar. 31, 2015
Goodwill [Roll Forward]
Goodwill, gross, beginning of year	$ 13,043us-gaap_GoodwillGross
Goodwill, impaired, accumulated impairment loss, beginning of year	(4,720)
Goodwill, net, beginning of year	8,323us-gaap_Goodwill
Goodwill recognized due to acquisitions	6,619us-gaap_GoodwillAcquiredDuringPeriod
Change in foreign exchange rates	(346)us-gaap_GoodwillTranslationAdjustments
Goodwill, gross, end of quarter	19,105us-gaap_GoodwillGross
Goodwill, impaired, accumulated impairment loss, end of quarter	(4,509)
Goodwill, net, end of quarter	14,596us-gaap_Goodwill
Solar
Goodwill [Roll Forward]
Goodwill, gross, beginning of year	12,315
Goodwill, impaired, accumulated impairment loss, beginning of year	(4,720)
Goodwill, net, beginning of year	7,595
Goodwill recognized due to acquisitions	2,272
Change in foreign exchange rates	(346)
Goodwill, gross, end of quarter	14,030
Goodwill, impaired, accumulated impairment loss, end of quarter	(4,509)
Goodwill, net, end of quarter	9,521
Semiconductor
Goodwill [Roll Forward]
Goodwill, gross, beginning of year	0
Goodwill, impaired, accumulated impairment loss, beginning of year	0
Goodwill, net, beginning of year	0
Goodwill recognized due to acquisitions	4,347
Change in foreign exchange rates	0
Goodwill, gross, end of quarter	4,347
Goodwill, impaired, accumulated impairment loss, end of quarter	0
Goodwill, net, end of quarter	4,347
Polishing
Goodwill [Roll Forward]
Goodwill, gross, beginning of year	728
Goodwill, impaired, accumulated impairment loss, beginning of year	0
Goodwill, net, beginning of year	728
Change in foreign exchange rates	0
Goodwill, gross, end of quarter	728
Goodwill, impaired, accumulated impairment loss, end of quarter	0
Goodwill, net, end of quarter	$ 728

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

+ Details

Name:	us-gaap_Goodwill
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillAcquiredDuringPeriod
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a,h)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillGross
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a,h)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillImpairedAccumulatedImpairmentLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

Name:	us-gaap_GoodwillRollForward
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (f)

-URI http://asc.fasb.org/extlink&oid=14024403&loc=d3e13816-109267

+ Details

Name:	us-gaap_GoodwillTranslationAdjustments
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=asys_PolishingSuppliesAndEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=asys_SemiconductorEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementBusinessSegmentsAxis=asys_SolarEquipmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: