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Goodwill and Other Intangible Assets - Narrative (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Oct. 31, 2018 | Oct. 31, 2019 | Oct. 31, 2018 | Oct. 31, 2017
Goodwill [Line Items] |  |  |  |
Goodwill impairment (recovery) |  | $ 0 | $ 20,300,000 | $ 0
Net impairment charge |  | $ 0 |  | $ 0
Technical Solutions |  |  |  |
Goodwill [Line Items] |  |  |  |
Goodwill impairment (recovery) | $ 20,300,000 |  | 20,300,000 |
Customer relationships | Technical Solutions |  |  |  |
Goodwill [Line Items] |  |  |  |
Net impairment charge |  |  | $ 6,200,000 |

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