Goodwill and Intangible Assets - Goodwill Impairment Test (Details) $ in Thousands	9 Months Ended
Jun. 30, 2020 USD ($)
Brooks Semiconductor Solutions Group
Goodwill [Line Items]
Goodwill impairment	$ 0
Brooks Life Sciences
Goodwill [Line Items]
Goodwill impairment	$ 0

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
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