Financial Information for Business Segments (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2011
Revenues
Product	$ 97,098	$ 161,189
Services	23,130	17,178
Total revenues	120,228	178,367
Gross profit	40,357	57,319
Operating income (loss)	1,463	23,729
Assets	621,804		636,620
Brooks Product Solutions
Revenues
Product	85,294	112,001
Total revenues	85,294	112,001
Gross profit	28,401	43,090
Operating income (loss)	1,085	17,471
Assets	217,841		235,322
Brooks Global Services
Revenues
Product	2,377	3,298
Services	19,717	17,178
Total revenues	22,094	20,476
Gross profit	7,136	7,267
Operating income (loss)	2,949	2,510
Assets	55,987		52,354
Brooks Life Science Systems
Revenues
Product	9,427
Services	3,413
Total revenues	12,840
Gross profit	4,820
Operating income (loss)	(633)
Assets	111,523		101,331
Contract Manufacturing
Revenues
Product		45,890
Total revenues		45,890
Gross profit		6,962
Operating income (loss)		4,643
Operating Segments, Total
Revenues
Product	97,098	161,189
Services	23,130	17,178
Total revenues	120,228	178,367
Gross profit	40,357	57,319
Operating income (loss)	3,401	24,624
Assets	$ 385,351		$ 389,007