REVENUES - Schedule of Disaggregation of Revenues (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Apr. 30, 2024	Apr. 30, 2023	Apr. 30, 2024	Apr. 30, 2023
Revenue from External Customer [Line Items]
Revenues	$ 2,018.2	$ 1,984.0	$ 4,087.8	$ 3,975.3
B&I
Revenue from External Customer [Line Items]
Revenues	989.6	998.5	2,022.8	2,035.0
M&D
Revenue from External Customer [Line Items]
Revenues	388.6	373.2	789.5	753.7
Education
Revenue from External Customer [Line Items]
Revenues	225.6	216.7	445.7	431.6
Aviation
Revenue from External Customer [Line Items]
Revenues	238.2	227.2	487.8	439.5
Technical Solutions
Revenue from External Customer [Line Items]
Revenues	176.2	168.4	342.1	315.5
Janitorial
Revenue from External Customer [Line Items]
Revenues	1,261.3	1,223.2	2,537.9	2,462.4
Janitorial | B&I
Revenue from External Customer [Line Items]
Revenues	681.5	673.5	1,374.7	1,360.6
Janitorial | M&D
Revenue from External Customer [Line Items]
Revenues	338.2	325.3	687.1	653.8
Janitorial | Education
Revenue from External Customer [Line Items]
Revenues	199.7	188.2	397.7	375.9
Janitorial | Aviation
Revenue from External Customer [Line Items]
Revenues	41.9	36.2	78.4	72.1
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	194.8	202.1	393.9	385.5
Parking | B&I
Revenue from External Customer [Line Items]
Revenues	102.5	100.3	205.7	197.1
Parking | M&D
Revenue from External Customer [Line Items]
Revenues	12.1	9.9	25.1	21.3
Parking | Education
Revenue from External Customer [Line Items]
Revenues	0.1	0.3	0.2	0.5
Parking | Aviation
Revenue from External Customer [Line Items]
Revenues	80.1	91.7	162.8	166.5
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	280.8	298.9	591.4	627.8
Facility Services | B&I
Revenue from External Customer [Line Items]
Revenues	205.7	224.7	442.3	477.3
Facility Services | M&D
Revenue from External Customer [Line Items]
Revenues	38.3	38.0	77.3	78.5
Facility Services | Education
Revenue from External Customer [Line Items]
Revenues	25.8	28.2	47.8	55.2
Facility Services | Aviation
Revenue from External Customer [Line Items]
Revenues	11.1	8.0	24.1	16.8
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	176.2	168.4	342.1	315.5
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	176.2	168.4	342.1	315.5
Airline Services
Revenue from External Customer [Line Items]
Revenues	105.1	91.3	222.5	184.1
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	105.1	91.3	222.5	184.1
Airline Services | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	$ 0.0	$ 0.0	$ 0.0	$ 0.0