Acquisitions - Escrow (Details) - BioStorage Technologies, Inc. - USD ($) $ in Millions	Jun. 30, 2017	Sep. 30, 2016	Nov. 30, 2015
Business Acquisition [Line Items]
Escrow deposit	$ 0.0		$ 5.4
Escrow reserve			2.9
Escrow deposit for acquiree's employees retention obligations	$ 0.0	$ 0.1	$ 2.5

Escrow Deposit for Acquiree's Employees Retention Obligations

No definition available.

Name:	brks_EscrowDepositforAcquireesEmployeesRetentionObligations
Namespace Prefix:	brks_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount in escrow reserved for potential future claims against sellers.

+ References

No definition available.

+ Details

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Namespace Prefix:	brks_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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

- Definition

The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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

- Details

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