Segment Information - Financial Information for Business Segments (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Sep. 30, 2015
Revenue
Product	$ 101,462	$ 116,395	$ 190,642	$ 216,125
Services	33,819	22,918	64,594	45,924
Total revenues	135,281	139,313	255,236	262,049
Gross profit	46,800	46,025	87,354	85,113
Segment operating income (loss)	(6,339)	3,053	(14,659)	(3,427)
Total assets	684,395		684,395		$ 759,654
Brooks Product Solutions
Revenue
Product	86,790	98,958	163,351	181,814
Services	0	0	0	0
Total revenues	86,790	98,958	163,351	181,814
Gross profit	30,570	33,995	57,671	60,917
Segment operating income (loss)	4,791	7,995	5,128	8,457
Total assets	277,897		277,897		260,011
Brooks Global Services
Revenue
Product	3,448	4,128	6,066	8,236
Services	18,581	18,709	38,478	37,798
Total revenues	22,029	22,837	44,544	46,034
Gross profit	6,373	7,043	13,931	15,506
Segment operating income (loss)	1,867	2,108	4,470	5,661
Total assets	51,545		51,545		57,058
Brooks Life Science Systems
Revenue
Product	11,224	13,309	21,225	26,075
Services	15,238	4,209	26,116	8,126
Total revenues	26,462	17,518	47,341	34,201
Gross profit	9,857	4,987	15,752	8,690
Segment operating income (loss)	(2,217)	(4,391)	(6,819)	(9,907)
Total assets	254,125		254,125		110,910
Operating Segments
Revenue
Product	101,462	116,395	190,642	216,125
Services	33,819	22,918	64,594	45,924
Total revenues	135,281	139,313	255,236	262,049
Gross profit	46,800	46,025	87,354	85,113
Segment operating income (loss)	4,441	$ 5,712	2,779	$ 4,211
Total assets	$ 583,567		$ 583,567		$ 427,979