v3.26.1
REVENUES - Schedule of Disaggregation of Revenues (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Jul. 31, 2026
Jul. 31, 2025
Jul. 31, 2026
Jul. 31, 2025
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues $ 2,317.1 $ 2,224.0 $ 6,850.6 $ 6,450.5
Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 1,665.3 1,667.8 5,016.8 4,873.4
Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 1,293.9 1,323.8 3,938.9 3,896.1
Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 162.6 134.5 444.2 368.2
Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 208.8 209.4 633.7 609.1
Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 651.8 556.2 1,833.8 1,577.1
Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 383.7 304.8 1,064.0 910.4
Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 268.1 251.4 769.8 666.8
B&I        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 1,012.2 1,038.7 3,093.2 3,077.2
B&I | Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 805.3 827.1 2,454.8 2,441.3
B&I | Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 698.4 715.5 2,133.4 2,119.9
B&I | Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
B&I | Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 106.9 111.6 321.4 321.4
B&I | Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 207.0 211.7 638.4 635.9
B&I | Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 205.7 210.5 634.3 632.0
B&I | Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 1.3 1.2 4.0 3.9
M&D        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 481.0 408.9 1,367.1 1,201.2
M&D | Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 338.8 356.9 1,052.9 1,049.8
M&D | Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 322.6 343.3 995.9 1,010.9
M&D | Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
M&D | Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 16.3 13.6 57.0 38.9
M&D | Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 142.1 52.0 314.2 151.4
M&D | Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 135.2 51.3 305.4 150.5
M&D | Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 6.9 0.7 8.8 0.9
Aviation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 328.1 291.8 936.6 822.0
Aviation | Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 313.0 278.8 893.0 782.7
Aviation | Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 64.9 60.1 193.9 166.0
Aviation | Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 162.6 134.5 444.2 368.2
Aviation | Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 85.6 84.2 254.9 248.4
Aviation | Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 15.1 12.9 43.6 39.3
Aviation | Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 15.1 12.9 43.6 39.3
Aviation | Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Education        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 235.8 235.1 696.7 688.2
Education | Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 208.1 205.0 616.1 599.6
Education | Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 208.0 204.9 615.8 599.3
Education | Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Education | Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.1 0.1 0.3 0.3
Education | Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 27.7 30.1 80.6 88.6
Education | Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 27.7 30.1 80.6 88.6
Education | Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 259.9 249.5 757.0 662.0
Technical Solutions | Facility Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Janitorial        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Aviation Services        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Parking and Transportation        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Engineering and Infrastructure Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 259.9 249.5 757.0 662.0
Technical Solutions | Operations and Maintenance        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Building & Energy Solutions        
Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Product and Service, Revenue [Line Items]        
Revenues $ 259.9 $ 249.5 $ 757.0 $ 662.0