Restructuring Charges - General Information (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		9 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Mar. 31, 2017	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2016	Sep. 30, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges		$ 996				$ 9,807
Restructuring reserve		5,789		$ 7,389		5,789		$ 2,073
Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 828	996			$ 2,663	9,782
Restructuring reserve	1,690	5,789	$ 2,044	7,293	1,690	5,789	$ 5,939	1,640
Facilities and other contract termination costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges						25
Restructuring reserve		0		96		0		$ 433
Brooks Life Science Systems | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		300			200
Brooks Semiconductor Solutions Group
Restructuring Cost and Reserve [Line Items]
Restructuring charges					2,200
Brooks Semiconductor Solutions Group | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges					2,200
Streamline Service Operations, Initiated Fiscal Year 2017
Restructuring Cost and Reserve [Line Items]
Restructuring charges	600
Restructuring reserve	800				800
Streamline Service Operations, Initiated Fiscal Year 2017 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges			$ 900
Restructuring expected cost	1,500				1,500
Streamline Service Operations, Initiated Fiscal Year 2017 | Brooks Semiconductor Solutions Group
Restructuring Cost and Reserve [Line Items]
Restructuring charges	600				1,500
Reduce Global Footprint and Streamline Cost Structure, Initiated Fiscal Year 2016
Restructuring Cost and Reserve [Line Items]
Restructuring charges	200				500
Restructuring reserve	900				900
Reduce Global Footprint and Streamline Cost Structure, Initiated Fiscal Year 2016 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges	200				500		1,800
Restructuring expected cost	2,500				2,500
Restructuring expected cost remaining	200				200
Reduce Global Footprint and Streamline Cost Structure, Initiated Fiscal Year 2016 | Brooks Semiconductor Solutions Group
Restructuring Cost and Reserve [Line Items]
Restructuring charges					700
Reduce Global Footprint and Streamline Cost Structure, Initiated Fiscal Year 2016 | Brooks Semiconductor Solutions Group | Facilities and other contract termination costs
Restructuring Cost and Reserve [Line Items]
Restructuring charges					700
Actions Initiated Prior to Fiscal Year 2017 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges					300
Actions Initiated Prior to Fiscal Year 2016
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	0				0
Actions Initiated Prior to Fiscal Year 2016 | Brooks Semiconductor Solutions Group
Restructuring Cost and Reserve [Line Items]
Restructuring charges					200		3,000
Restructuring cost incurred to date	3,200				3,200
Actions Initiated Prior to Fiscal Year 2016 | Brooks Semiconductor Solutions Group | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges					200
Streamline Business Operations, Initiated Prior to Fiscal Year 2017
Restructuring Cost and Reserve [Line Items]
Restructuring reserve	0				0
Streamline Business Operations, Initiated Prior to Fiscal Year 2017 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		600			300	5,800	$ 5,800
Restructuring cost incurred to date	$ 6,100				$ 6,100
Streamlining Segment Structure, Integrating Acquisition, and Facility Closure, Initiated in Fiscal Year 2016 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges						1,200
Restructuring reserve		0				0
Streamlining Segment Structure, Integrating Acquisition, and Facility Closure, Initiated in Fiscal Year 2016 | Brooks Life Science Systems | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges		300		$ 2,400
Restructuring expected cost remaining		2,800				2,800
Streamlining Segment Structure, Integrating Acquisition, and Facility Closure, Initiated in Fiscal Year 2016 | Brooks Semiconductor Solutions Group
Restructuring Cost and Reserve [Line Items]
Restructuring charges						1,200
Actions Initiated During June 2016 | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring charges						8,500
Actions Initiated During June 2016 | Brooks Life Science Systems | Workforce-related termination benefits
Restructuring Cost and Reserve [Line Items]
Restructuring expected cost		$ 2,800				$ 2,800