Joint Ventures - Additional Information (Detail) (USD $)	3 Months Ended							6 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Mar. 31, 2012	Mar. 31, 2011	Jun. 30, 2012	Jun. 30, 2011	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2009
Schedule of Equity Method Investments [Line Items]
Equity in earnings (losses) of joint ventures	$ 196,000	$ 430,000	$ 1,050,000	$ 1,758,000	$ 1,632,000	$ 646,000	$ 779,000	$ 1,480,000	$ 1,425,000	$ 1,676,000	$ 3,057,000	$ 4,815,000	$ 1,074,000	$ 33,000
Equity investment in joint ventures, carrying value	35,785,000			34,950,000						35,785,000		34,950,000
ULVAC Cryogenics, Inc.
Schedule of Equity Method Investments [Line Items]
Equity in earnings (losses) of joint ventures	400,000				1,400,000					1,800,000	2,900,000
Equity investment in joint ventures, carrying value	32,000,000									32,000,000
Management fee payments received	200,000				200,000					800,000	700,000
Charges incurred for products or services	200,000				300,000					700,000	500,000
Accounts payable for unpaid products and services	0			100,000						0		100,000
Percentage of interest in joint venture	50.00%				50.00%					50.00%	50.00%
Yaskawa Brooks Automation, Inc.
Schedule of Equity Method Investments [Line Items]
Equity in earnings (losses) of joint ventures	(100,000)				200,000					(100,000)	200,000
Equity investment in joint ventures, carrying value	3,700,000									3,700,000
Charges incurred for products or services	100,000				100,000					300,000	400,000
Accounts payable for unpaid products and services	100,000			100,000						100,000		100,000
Percentage of interest in joint venture	50.00%				50.00%					50.00%	50.00%
Revenues earned from joint ventures	1,700,000				1,600,000					5,700,000	7,600,000
Amount due from joint ventures	$ 2,000,000			$ 2,200,000						$ 2,000,000		$ 2,200,000