REVENUES - Disaggregation of Revenue (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2023	Jan. 31, 2022
Revenue from External Customer [Line Items]
Revenues	$ 1,991.3	$ 1,936.2
B&I
Revenue from External Customer [Line Items]
Revenues	1,036.6	1,029.5
M&D
Revenue from External Customer [Line Items]
Revenues	380.5	359.1
Education
Revenue from External Customer [Line Items]
Revenues	214.9	205.7
Aviation
Revenue from External Customer [Line Items]
Revenues	212.3	200.3
Technical Solutions
Revenue from External Customer [Line Items]
Revenues	147.0	141.8
Janitorial
Revenue from External Customer [Line Items]
Revenues	1,239.9	1,190.2
Janitorial | B&I
Revenue from External Customer [Line Items]
Revenues	687.0	677.9
Janitorial | M&D
Revenue from External Customer [Line Items]
Revenues	329.3	304.2
Janitorial | Education
Revenue from External Customer [Line Items]
Revenues	187.7	178.3
Janitorial | Aviation
Revenue from External Customer [Line Items]
Revenues	35.9	29.8
Janitorial | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Parking
Revenue from External Customer [Line Items]
Revenues	182.6	172.0
Parking | B&I
Revenue from External Customer [Line Items]
Revenues	96.9	83.2
Parking | M&D
Revenue from External Customer [Line Items]
Revenues	10.7	10.7
Parking | Education
Revenue from External Customer [Line Items]
Revenues	0.3	0.3
Parking | Aviation
Revenue from External Customer [Line Items]
Revenues	74.8	77.7
Parking | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Facility Services
Revenue from External Customer [Line Items]
Revenues	328.8	346.0
Facility Services | B&I
Revenue from External Customer [Line Items]
Revenues	252.6	268.4
Facility Services | M&D
Revenue from External Customer [Line Items]
Revenues	40.5	44.1
Facility Services | Education
Revenue from External Customer [Line Items]
Revenues	27.0	27.1
Facility Services | Aviation
Revenue from External Customer [Line Items]
Revenues	8.8	6.5
Facility Services | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Building & Energy Solutions
Revenue from External Customer [Line Items]
Revenues	147.0	141.8
Building & Energy Solutions | B&I
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Building & Energy Solutions | M&D
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Building & Energy Solutions | Education
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Building & Energy Solutions | Aviation
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Building & Energy Solutions | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	147.0	141.8
Airline Services
Revenue from External Customer [Line Items]
Revenues	92.8	86.3
Airline Services | B&I
Revenue from External Customer [Line Items]
Revenues	0.0
Airline Services | M&D
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Airline Services | Education
Revenue from External Customer [Line Items]
Revenues	0.0	0.0
Airline Services | Aviation
Revenue from External Customer [Line Items]
Revenues	92.8	86.3
Airline Services | Technical Solutions
Revenue from External Customer [Line Items]
Revenues	$ 0.0	$ 0.0