REVENUES - Schedule of Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2025	Jan. 31, 2024
Revenue from External Customer [Line Items]
Revenues	$ 2,114.9	$ 2,069.6
Facility Solutions
Revenue from External Customer [Line Items]
Revenues	1,598.0	1,592.2
Janitorial
Revenue from External Customer [Line Items]
Revenues	1,276.4	1,275.8
Aviation Services
Revenue from External Customer [Line Items]
Revenues	117.3	117.4
Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	204.3	199.1
Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	516.9	477.3
Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	314.6	311.4
Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	202.3	165.9
B&I
Revenue from External Customer [Line Items]
Revenues	1,022.9	1,033.1
B&I | Facility Solutions
Revenue from External Customer [Line Items]
Revenues	802.3	795.7
B&I | Janitorial
Revenue from External Customer [Line Items]
Revenues	697.8	692.4
B&I | Aviation Services
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
B&I | Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	104.5	103.3
B&I | Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	220.6	237.4
B&I | Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	220.6	237.4
B&I | Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
M&D
Revenue from External Customer [Line Items]
Revenues	394.3	400.9
M&D | Facility Solutions
Revenue from External Customer [Line Items]
Revenues	341.6	361.9
M&D | Janitorial
Revenue from External Customer [Line Items]
Revenues	328.3	348.9
M&D | Aviation Services
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
M&D | Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	13.3	13.0
M&D | Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	52.7	39.0
M&D | Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	52.7	39.0
M&D | Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Education
Revenue from External Customer [Line Items]
Revenues	225.3	220.1
Education | Facility Solutions
Revenue from External Customer [Line Items]
Revenues	197.2	198.1
Education | Janitorial
Revenue from External Customer [Line Items]
Revenues	197.1	198.0
Education | Aviation Services
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Education | Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	0.1	0.1
Education | Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	28.1	22.0
Education | Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	28.1	22.0
Education | Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Aviation
Revenue from External Customer [Line Items]
Revenues	270.1	249.5
Aviation | Facility Solutions
Revenue from External Customer [Line Items]
Revenues	256.9	236.6
Aviation | Janitorial
Revenue from External Customer [Line Items]
Revenues	53.3	36.5
Aviation | Aviation Services
Revenue from External Customer [Line Items]
Revenues	117.3	117.4
Aviation | Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	86.3	82.7
Aviation | Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	13.2	13.0
Aviation | Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	13.2	13.0
Aviation | Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions
Revenue from External Customer [Line Items]
Revenues	202.3	165.9
Technical Solutions | Facility Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions | Janitorial
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions | Aviation Services
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions | Parking and Transportation
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions | Engineering and Infrastructure Solutions
Revenue from External Customer [Line Items]
Revenues	202.3	165.9
Technical Solutions | Operations and Maintenance
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Technical Solutions | Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	$ 202.3	$ 165.9