Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2017	Jul. 31, 2016	Jul. 31, 2017	Jul. 31, 2016
Income Statement [Abstract]
Revenues	$ 1,318.4	$ 1,296.9	$ 3,955.6	$ 3,822.4
Operating expenses	1,184.5	1,161.3	3,544.1	3,430.1
Selling, general and administrative expenses	101.3	108.0	299.2	310.2
Amortization of intangible assets	6.1	5.8	17.4	18.8
Restructuring and related expenses	5.2	3.3	16.0	19.3
Impairment recovery and gain on sale	(1.1)	0.0	(18.5)	0.0
Operating profit	22.6	18.5	97.4	44.0
Income from unconsolidated affiliates, net	1.2	2.1	3.6	5.3
Interest expense	(2.8)	(2.6)	(9.1)	(7.7)
Income from continuing operations before income taxes	21.0	18.0	91.9	41.6
Income tax benefit (provision)	11.9	14.9	(11.3)	11.7
Income from continuing operations	32.9	32.9	80.6	53.3
Net loss from discontinued operations	0.0	(1.8)	(73.2)	(3.9)
Net income	32.9	31.1	7.4	49.4
Other comprehensive income (loss)
Foreign currency translation	3.6	(12.6)	9.8	(17.0)
Other, net of taxes	(0.2)	(0.6)	1.4	(0.5)
Comprehensive income	$ 36.3	$ 17.9	$ 18.6	$ 31.9
Net income per common share — Basic
Income from continuing operations (in usd per share)	$ 0.59	$ 0.58	$ 1.44	$ 0.94
Loss from discontinued operations (in usd per share)	0.00	(0.03)	(1.31)	(0.06)
Net income (in usd per share)	0.59	0.55	0.13	0.88
Net income per common share — Diluted
Income from continuing operations (in usd per share)	0.58	0.58	1.42	0.94
Loss from discontinued operations (in usd per share)	0.00	(0.03)	(1.29)	(0.07)
Net income (in usd per share)	$ 0.58	$ 0.55	$ 0.13	$ 0.87
Weighted-average common and common equivalent shares outstanding
Basic (in shares)	56.1	56.2	56.0	56.4
Diluted (in shares)	56.6	56.8	56.6	56.9
Dividends declared per common share (in usd per share)	$ 0.170	$ 0.165	$ 0.51	$ 0.495