Joint Ventures Narrative (Detail) (USD $)	3 Months Ended		6 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2013	Mar. 31, 2012	Sep. 30, 2012
Schedule of Equity Method Investments [Line Items]
Equity in earnings (losses) of joint ventures	$ (10,000)	$ 430,000	$ (16,000)	$ 1,480,000
Equity investment in joint ventures	28,425,000		28,425,000		31,428,000
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	(16,000)	600,000	62,000	1,500,000
Equity investment in joint ventures	25,100,000		25,100,000
Management fee payments received	100,000	200,000	200,000	600,000
Charges incurred from related parties	100,000	200,000	400,000	500,000
Accounts payable for unpaid products and services	34,000		34,000		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	6,000	(200,000)	(78,000)	5,000
Equity investment in joint ventures	3,300,000		3,300,000
Charges incurred from related parties	200,000	100,000	300,000	200,000
Accounts payable for unpaid products and services	100,000		100,000		100,000
Revenues earned from joint ventures	1,300,000	1,900,000	2,900,000	4,000,000
Due from joint venture	$ 1,400,000	$ 2,000,000	$ 1,400,000	$ 2,000,000