Goodwill and Intangible Assets Disclosure [Line Items]

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- Definition

Number of Reporting Units with Goodwill

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to property, plant, and equipment acquired in connection with a business combination for which the initial accounting was incomplete.

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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.

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+ Details

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- 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.

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Number of reporting units tested for impairment of goodwill. A reporting unit is an operating segment or one level below an operating segment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Reporting Unit
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- Definition

Percentage of fair value of reporting unit in excess of carrying amount.

+ References

No definition available.

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Goodwill and Intangible Assets - Additional Information (Detail)		6 Months Ended	9 Months Ended	12 Months Ended
	Feb. 01, 2016 USD ($)	Mar. 31, 2016 reporting_unit	Jun. 30, 2016 reporting_unit	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2013 USD ($)	Apr. 01, 2016	Nov. 30, 2015 USD ($)	Aug. 14, 2015 USD ($)
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit		6	5
Number of reporting units with goodwill \| reporting_unit		5
Carrying amount of goodwill				$ 202,138,000	$ 121,408,000	$ 109,501,000
Impairment loss				0	0	398,000
Amortization expense for intangible assets				15,000,000	12,900,000	10,600,000
BioStorage Technologies, Inc.
Goodwill and Intangible Assets Disclosure [Line Items]
Carrying amount of goodwill									$ 79,639,000
Goodwill, acquired during period				79,700,000
Amortization expense for intangible assets				2,900,000
Contact Co., Ltd
Goodwill and Intangible Assets Disclosure [Line Items]
Carrying amount of goodwill										$ 4,195,000
Measurement period adjustment				(1,100,000)
Amortization expense for intangible assets				700,000
CeligoCell Cytometer product line
Goodwill and Intangible Assets Disclosure [Line Items]
Impairment loss						400,000	$ 2,000,000
Brooks Product Solutions
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit		4
Brooks Semiconductor Solutions Group
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit			4
Carrying amount of goodwill				66,837,000	65,783,000	62,123,000
Brooks Life Science Systems
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit			1
Carrying amount of goodwill				135,301,000	$ 55,625,000	$ 47,378,000
Polycold and CTI Cryogenics Reporting Units
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit		2
BSSG Cryogenics Reporting Unit
Goodwill and Intangible Assets Disclosure [Line Items]
Number of reporting units \| reporting_unit		1
Carrying amount of goodwill				$ 24,000,000
Polycold Reporting Unit
Goodwill and Intangible Assets Disclosure [Line Items]
Carrying amount of goodwill	$ 24,000,000
Percentage of fair value in excess of carrying amount	18.00%		12.00%					12.00%
Goodwill, impairment loss	$ 0