Intangible assets (Detail) - USD ($) $ in Thousands	Oct. 31, 2016	Oct. 31, 2015
Intangible Assets [Line Items]
Amortizable intangible assets, net	$ 3,619	$ 4,268
Non-amortizable intangible assets, trade marks	1,237	1,387
Non-compete agreements (estimated lives 3 - 5 years)
Intangible Assets [Line Items]
Amortizable intangible assets, gross	310	310
Amortizable intangible assets, accumulated amortization	(273)	(212)
Amortizable intangible assets, net	37	98
Customer relationships (estimated lives 7 - 15 years)
Intangible Assets [Line Items]
Amortizable intangible assets, gross	5,099	5,099
Amortizable intangible assets, accumulated amortization	(1,644)	(1,101)
Amortizable intangible assets, net	3,455	3,998
Backlog (estimated life 1 year)
Intangible Assets [Line Items]
Amortizable intangible assets, gross	134	134
Amortizable intangible assets, accumulated amortization	(134)	(100)
Amortizable intangible assets, net	0	34
Patents (estimated life 14 years)
Intangible Assets [Line Items]
Amortizable intangible assets, gross	142	142
Amortizable intangible assets, accumulated amortization	(15)	(4)
Amortizable intangible assets, net	$ 127	$ 138