Goodwill and Intangible Assets Components of Goodwill by Business Segment (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Sep. 30, 2014
Goodwill [Line Items]
Gross goodwill at beginning of period		$ 724,459us-gaap_GoodwillGross
Less: aggregate impairment charges recorded		(614,958)
Goodwill [Roll Forward]
Acquisitions and adjustments during the period	8,151
Goodwill, less accumulated impairments at end of period	117,652us-gaap_Goodwill	109,501us-gaap_Goodwill
Brooks Product Solutions
Goodwill [Line Items]
Gross goodwill at beginning of period		494,275
Less: aggregate impairment charges recorded		(437,706)
Goodwill [Roll Forward]
Acquisitions and adjustments during the period	301
Goodwill, less accumulated impairments at end of period	56,870	56,569
Brooks Global Services
Goodwill [Line Items]
Gross goodwill at beginning of period		156,792
Less: aggregate impairment charges recorded		(151,238)
Goodwill [Roll Forward]
Acquisitions and adjustments during the period	0
Goodwill, less accumulated impairments at end of period	5,554	5,554
Brooks Life Science Systems
Goodwill [Line Items]
Gross goodwill at beginning of period		47,378
Less: aggregate impairment charges recorded		0
Goodwill [Roll Forward]
Acquisitions and adjustments during the period	7,850
Goodwill, less accumulated impairments at end of period	55,228	47,378
Other
Goodwill [Line Items]
Gross goodwill at beginning of period		26,014
Less: aggregate impairment charges recorded		(26,014)
Goodwill [Roll Forward]
Acquisitions and adjustments during the period	0
Goodwill, less accumulated impairments at end of period	$ 0	$ 0

Goodwill Acquired During Period And Adjustments

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- Definition

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.

+ References

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=35741047&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

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- 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=35741047&loc=d3e13816-109267

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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

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