Segment Information - Reportable Operating Segments (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
Apr. 30, 2015	Apr. 30, 2014	Apr. 30, 2015	Apr. 30, 2014
Segment Reporting Information
Revenues	$ 1,270.1us-gaap_SalesRevenueServicesNet	$ 1,231.3us-gaap_SalesRevenueServicesNet	$ 2,559.5us-gaap_SalesRevenueServicesNet	$ 2,457.8us-gaap_SalesRevenueServicesNet
Operating profit	30.8us-gaap_OperatingIncomeLoss	27.9us-gaap_OperatingIncomeLoss	50.0us-gaap_OperatingIncomeLoss	51.8us-gaap_OperatingIncomeLoss
Income from unconsolidated affiliates, net	2.2	1.2	3.7	2.7
Interest expense	(2.5)us-gaap_InterestExpense	(2.7)us-gaap_InterestExpense	(5.2)us-gaap_InterestExpense	(5.4)us-gaap_InterestExpense
Income before income taxes	30.5	26.4	48.5	49.1
Janitorial
Segment Reporting Information
Revenues	659.5	631.7	1,325.5	1,268.8
Operating profit	39.9	37.2	74.8	67.5
Facility Services
Segment Reporting Information
Revenues	145.8	149.5	302.0	301.2
Operating profit	6.6	5.0	12.5	10.1
Parking
Segment Reporting Information
Revenues	153.5	152.6	309.2	302.9
Operating profit	6.7	6.0	13.2	11.2
Security
Segment Reporting Information
Revenues	93.7	93.8	188.6	193.5
Operating profit	2.6	2.0	4.5	4.3
Building & Energy Solutions
Segment Reporting Information
Revenues	121.5	118.5	240.9	220.6
Operating profit	3.2	3.5	4.4	6.2
Income from unconsolidated affiliates, net	(2.2)	(1.2)	(3.7)	(2.7)
Other
Segment Reporting Information
Revenues	96.1	85.2	193.3	170.8
Operating profit	3.0	2.4	5.6	4.3
Corporate
Segment Reporting Information
Operating profit	(29.0)	(27.0)	(61.3)	(49.1)
Operating Profit \| Janitorial
Segment Reporting Information
Impact of the change in reported operating profit		1.0		2.2
Operating Profit \| Facility Services
Segment Reporting Information
Impact of the change in reported operating profit		(0.4)		(0.8)
Operating Profit \| Parking
Segment Reporting Information
Impact of the change in reported operating profit		(0.4)		(0.9)
Operating Profit \| Security
Segment Reporting Information
Impact of the change in reported operating profit		$ (0.2)		$ (0.5)

This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of the cost of borrowed funds accounted for as interest expense.

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The net result for the period of deducting operating expenses from operating revenues.

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