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Basis of Presentation and Significant Accounting Policies (Tables) | 12 Months Ended
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Oct. 31, 2021
Accounting Policies [Abstract] |
Schedule of Estimated Useful Lives of Property, Plant and Equipment | We determine depreciation for financial reporting purposes using the straight-line method over the following estimated useful lives:
Category | Years
Computer equipment and software | 3–5
Machinery and other equipment | 3–5
Transportation equipment | 1.5–10
Buildings | 10–40
Furniture and fixtures | 5
Schedule of Management Reimbursement Revenue by Segment | Management Reimbursement Revenue by Segment
| Years Ended October 31,
(in millions) | 2021 |  | 2020 |  | 2019
Business & Industry | $ | 185.8 |  |  | $ | 221.4 |  |  | $ | 283.1 |
Aviation | 54.5 |  |  | 74.3 |  |  | 95.5 |
Total | $ | 240.3 |  |  | $ | 295.6 |  |  | $ | 378.7 |

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