Components of Goodwill by Business Segment (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Goodwill [Line Items]
Goodwill Beginning Balance	$ 699,685	$ 663,096
Acquisitions and adjustments during fiscal year	3,713	36,589
Goodwill Ending Balance	703,398	699,685
Accumulated Goodwill Impairments Beginning Balance	(614,958)	(614,958)
Impairments recorded during fiscal year
Accumulated Goodwill Impairments Ending Balance	(614,958)	(614,958)
Goodwill	88,440	84,727
Brooks Product Solutions
Goodwill [Line Items]
Goodwill Beginning Balance	485,844	485,844
Goodwill Ending Balance	485,844	485,844
Accumulated Goodwill Impairments Beginning Balance	(437,706)	(437,706)
Impairments recorded during fiscal year
Accumulated Goodwill Impairments Ending Balance	(437,706)	(437,706)
Goodwill	48,138	48,138
Brooks Global Services
Goodwill [Line Items]
Goodwill Beginning Balance	151,238	151,238
Goodwill Ending Balance	151,238	151,238
Accumulated Goodwill Impairments Beginning Balance	(151,238)	(151,238)
Impairments recorded during fiscal year
Accumulated Goodwill Impairments Ending Balance	(151,238)	(151,238)
Brooks Life Science Systems
Goodwill [Line Items]
Goodwill Beginning Balance	36,589
Acquisitions and adjustments during fiscal year	3,713	36,589
Goodwill Ending Balance	40,302	36,589
Impairments recorded during fiscal year
Goodwill	40,302	36,589
Contract Manufacturing
Goodwill [Line Items]
Goodwill Beginning Balance	18,593	18,593
Goodwill Ending Balance	18,593	18,593
Accumulated Goodwill Impairments Beginning Balance	(18,593)	(18,593)
Impairments recorded during fiscal year
Accumulated Goodwill Impairments Ending Balance	(18,593)	(18,593)
Other
Goodwill [Line Items]
Goodwill Beginning Balance	7,421	7,421
Goodwill Ending Balance	7,421	7,421
Accumulated Goodwill Impairments Beginning Balance	(7,421)	(7,421)
Impairments recorded during fiscal year
Accumulated Goodwill Impairments Ending Balance	$ (7,421)	$ (7,421)