Joint Ventures - Additional Information (Detail) (USD $)	3 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Sep. 30, 2011
Schedule of Equity Method Investments [Line Items]
Equity in earnings (losses) of joint ventures	$ 1,225,000	$ 310,000
Equity investment in joint ventures, carrying value	35,357,000		34,612,000
ULVAC Cryogenics, Inc.
Schedule of Equity Method Investments [Line Items]
Joint venture interest, percentage	50.00%	50.00%
Equity in earnings (losses) of joint ventures	1,000,000	200,000
Management fee payments received	400,000	200,000
Charges incurred for products or services	300,000	100,000
Accounts payable for unpaid products and services	200,000		100,000
Equity investment in joint ventures, carrying value	31,100,000
Yaskawa Brooks Automation, Inc.
Schedule of Equity Method Investments [Line Items]
Joint venture interest, percentage	50.00%	50.00%
Equity in earnings (losses) of joint ventures	200,000	100,000
Revenues earned from joint ventures	2,100,000	3,300,000
Amount due from joint ventures	2,300,000		2,200,000
Charges incurred for products or services	100,000	100,000
Accounts payable for unpaid products and services	100,000		100,000
Equity investment in joint ventures, carrying value	$ 4,300,000