Segment Information - Financial Information by Reportable Segment (Details) - USD ($) $ in Millions	3 Months Ended
	Jan. 31, 2018	Jan. 31, 2017
Revenues
Revenues	$ 1,588.3	$ 1,326.7
Operating profit (loss)
Operating profit (loss)	19.5	23.8
Adjustment for income from unconsolidated affiliates, net, included in Aviation and Government Services	0.5	1.4
Interest expense	(14.3)	(3.2)
Income from continuing operations before income taxes	5.8	22.0
Corporate
Operating profit (loss)
Operating profit (loss)	(47.4)	(34.6)
Segment Reconciling Items
Operating profit (loss)
Adjustment for tax deductions for energy efficient government buildings, included in Technical Solutions	(0.3)	(0.5)
Adjustment for income from unconsolidated affiliates, net, included in Aviation and Government Services	(0.6)	(1.3)
Business & Industry | Operating Segments
Revenues
Revenues	722.1	655.6
Operating profit (loss)
Operating profit (loss)	28.5	27.1
Aviation | Operating Segments
Revenues
Revenues	256.2	231.9
Operating profit (loss)
Operating profit (loss)	5.8	4.6
Technology & Manufacturing | Operating Segments
Revenues
Revenues	232.0	171.5
Operating profit (loss)
Operating profit (loss)	16.9	12.6
Education | Operating Segments
Revenues
Revenues	206.3	67.0
Operating profit (loss)
Operating profit (loss)	9.2	3.6
Technical Solutions | Operating Segments
Revenues
Revenues	104.0	107.7
Operating profit (loss)
Operating profit (loss)	5.5	7.9
Healthcare | Operating Segments
Revenues
Revenues	67.7	61.7
Operating profit (loss)
Operating profit (loss)	2.7	2.5
Government Services | Operating Segments
Revenues
Revenues	0.0	31.4
Operating profit (loss)
Operating profit (loss)	$ (0.7)	$ 1.9