v3.25.1
REVENUES - Schedule of Disaggregation of Revenues (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Apr. 30, 2025
Apr. 30, 2024
Apr. 30, 2025
Apr. 30, 2024
Revenue from External Customer [Line Items]        
Revenues $ 2,111.7 $ 2,018.2 $ 4,226.6 $ 4,087.8
Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 1,609.2 1,561.2 3,206.5 3,154.1
Janitorial        
Revenue from External Customer [Line Items]        
Revenues 1,296.5 1,261.3 2,572.3 2,537.9
Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 116.4 105.1 233.7 222.5
Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 196.3 194.8 400.5 393.9
Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 502.5 457.0 1,020.1 933.6
Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 292.4 280.8 607.7 591.4
Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues 210.2 176.2 412.4 342.1
B&I        
Revenue from External Customer [Line Items]        
Revenues 1,015.5 989.6 2,038.4 2,022.8
B&I | Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 812.8 783.9 1,615.1 1,580.4
B&I | Janitorial        
Revenue from External Customer [Line Items]        
Revenues 706.6 681.5 1,404.4 1,374.7
B&I | Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
B&I | Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 106.2 102.5 210.7 205.7
B&I | Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 202.7 205.7 423.4 442.3
B&I | Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 202.7 205.7 423.4 442.3
B&I | Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
M&D        
Revenue from External Customer [Line Items]        
Revenues 398.1 388.6 792.4 789.5
M&D | Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 351.4 350.3 692.9 712.2
M&D | Janitorial        
Revenue from External Customer [Line Items]        
Revenues 339.3 338.2 667.5 687.1
M&D | Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
M&D | Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 12.1 12.1 25.4 25.1
M&D | Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 46.7 38.3 99.4 77.3
M&D | Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 46.7 38.3 99.4 77.3
M&D | Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Aviation        
Revenue from External Customer [Line Items]        
Revenues 260.1 238.2 530.2 487.8
Aviation | Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 246.9 227.1 503.9 463.7
Aviation | Janitorial        
Revenue from External Customer [Line Items]        
Revenues 52.7 41.9 105.9 78.4
Aviation | Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 116.4 105.1 233.7 222.5
Aviation | Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 77.9 80.1 164.2 162.8
Aviation | Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 13.2 11.1 26.3 24.1
Aviation | Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 13.2 11.1 26.3 24.1
Aviation | Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Education        
Revenue from External Customer [Line Items]        
Revenues 227.8 225.6 453.2 445.7
Education | Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 198.0 199.8 394.6 397.9
Education | Janitorial        
Revenue from External Customer [Line Items]        
Revenues 197.9 199.7 394.4 397.7
Education | Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Education | Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 0.1 0.1 0.2 0.2
Education | Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 29.8 25.8 58.5 47.8
Education | Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 29.8 25.8 58.5 47.8
Education | Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions        
Revenue from External Customer [Line Items]        
Revenues 210.2 176.2 412.4 342.1
Technical Solutions | Facility Solutions        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Janitorial        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Aviation Services        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Parking and Transportation        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Engineering and Infrastructure Solutions        
Revenue from External Customer [Line Items]        
Revenues 210.2 176.2 412.4 342.1
Technical Solutions | Operations and Maintenance        
Revenue from External Customer [Line Items]        
Revenues 0.0 0.0 0.0 0.0
Technical Solutions | Building & Energy Solutions        
Revenue from External Customer [Line Items]        
Revenues $ 210.2 $ 176.2 $ 412.4 $ 342.1