REVENUES - Schedule of Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2024	Jul. 31, 2023
Revenue from External Customer [Line Items]
Revenues	$ 2,094.2	$ 2,028.2	$ 6,182.0	$ 6,003.5
B&I
Revenue from External Customer [Line Items]
Revenues	1,010.6	1,021.4	3,033.4	3,056.4
M&D
Revenue from External Customer [Line Items]
Revenues	377.1	381.9	1,166.6	1,135.5
Education
Revenue from External Customer [Line Items]
Revenues	228.3	219.1	674.0	650.7
Aviation
Revenue from External Customer [Line Items]
Revenues	268.4	238.0	756.1	677.5
Technical Solutions
Revenue from External Customer [Line Items]
Revenues	209.7	167.9	551.9	483.4
Janitorial
Revenue from External Customer [Line Items]
Revenues	1,277.0	1,277.8	3,814.8	3,740.0
Janitorial | B&I
Revenue from External Customer [Line Items]
Revenues	696.1	687.5	2,070.7	2,047.8
Janitorial | M&D
Revenue from External Customer [Line Items]
Revenues	326.5	334.8	1,013.5	988.6
Janitorial | Education
Revenue from External Customer [Line Items]
Revenues	200.6	218.6	598.4	594.5
Janitorial | Aviation
Revenue from External Customer [Line Items]
Revenues	53.7	36.9	132.1	109.0
Janitorial | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Parking
Revenue from External Customer [Line Items]
Revenues	203.6	196.9	597.5	582.3
Parking | B&I
Revenue from External Customer [Line Items]
Revenues	106.0	106.1	311.8	303.3
Parking | M&D
Revenue from External Customer [Line Items]
Revenues	12.8	9.9	38.0	31.3
Parking | Education
Revenue from External Customer [Line Items]
Revenues	0.1	0.2	0.3	0.7
Parking | Aviation
Revenue from External Customer [Line Items]
Revenues	84.6	80.6	247.5	247.1
Parking | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Facility Services
Revenue from External Customer [Line Items]
Revenues	285.1	272.6	876.6	900.6
Facility Services | B&I
Revenue from External Customer [Line Items]
Revenues	208.5	227.7	650.8	705.3
Facility Services | M&D
Revenue from External Customer [Line Items]
Revenues	37.8	37.2	115.1	115.7
Facility Services | Education
Revenue from External Customer [Line Items]
Revenues	27.6	0.3	75.4	55.5
Facility Services | Aviation
Revenue from External Customer [Line Items]
Revenues	11.2	7.4	35.3	24.2
Facility Services | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	209.7	167.9	551.9	483.4
Building & Energy Solutions | B&I
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Building & Energy Solutions | M&D
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Building & Energy Solutions | Education
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Building & Energy Solutions | Aviation
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Building & Energy Solutions | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	209.7	167.9	551.9	483.4
Airline Services
Revenue from External Customer [Line Items]
Revenues	118.8	113.0	341.2	297.2
Airline Services | B&I
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Airline Services | M&D
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Airline Services | Education
Revenue from External Customer [Line Items]
Revenues	0.0	0.0	0.0	0.0
Airline Services | Aviation
Revenue from External Customer [Line Items]
Revenues	118.8	113.0	341.2	297.2
Airline Services | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	$ 0.0	$ 0.0	$ 0.0	$ 0.0