Consolidated Statements of Comprehensive Income (Unaudited) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jul. 31, 2016	Jul. 31, 2015	Jul. 31, 2016	Jul. 31, 2015
Income Statement [Abstract]
Revenues	$ 1,296.9	$ 1,249.9	$ 3,822.4	$ 3,620.8
Expenses
Operating	1,166.5	1,156.3	3,445.2	3,281.9
Selling, general and administrative	102.8	92.8	295.1	282.1
Restructuring and related	3.3	2.2	19.3	2.2
Amortization of intangible assets	5.8	6.2	18.8	18.2
Total expenses	1,278.4	1,257.5	3,778.4	3,584.4
Operating profit (loss)	18.5	(7.6)	44.0	36.4
Income from unconsolidated affiliates, net	2.1	2.6	5.3	6.3
Interest expense	(2.6)	(2.4)	(7.7)	(7.6)
Income (loss) from continuing operations before income taxes	18.0	(7.4)	41.6	35.1
Income tax benefit (provision)	14.9	8.6	11.7	(3.6)
Income from continuing operations	32.9	1.2	53.3	31.5
Net (loss) income from discontinued operations	(1.8)	0.3	(3.9)	6.0
Net income	31.1	1.5	49.4	37.5
Other comprehensive income (loss):
Foreign currency translation	(12.6)	0.1	(17.0)	(1.6)
Other	(0.6)	0.1	(0.5)	0.1
Comprehensive income	$ 17.9	$ 1.7	$ 31.9	$ 36.0
Net income per common share — Basic:
Income from continuing operations (in dollars per share)	$ 0.58	$ 0.02	$ 0.94	$ 0.56
(Loss) income from discontinued operations (in dollars per share)	(0.03)	0.01	(0.06)	0.10
Net income (in dollars per share)	0.55	0.03	0.88	0.66
Net income per common share — Diluted:
Income from continuing operations (in dollars per share)	0.58	0.02	0.94	0.55
(Loss) income from discontinued operations (in dollars per share)	(0.03)	0.01	(0.07)	0.10
Net income (in dollars per share)	$ 0.55	$ 0.03	$ 0.87	$ 0.65
Weighted-average common and common equivalent shares outstanding
Basic (in shares)	56.2	56.8	56.4	56.7
Diluted (in shares)	56.8	57.5	56.9	57.4
Dividends declared per common share (in dollars per share)	$ 0.165	$ 0.160	$ 0.495	$ 0.480