Intangible assets - Additional Information (Detail) - USD ($)		3 Months Ended	12 Months Ended
Jan. 01, 2020	Jan. 31, 2020	Oct. 31, 2019
Intangible assets
Amortization expense		$ 173,000	$ 275,000
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	8 years 4 months 21 days

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
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-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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