Segment Information - Financial Information by Reportable Segment (Details) - USD ($) $ in Millions	3 Months Ended
Jan. 31, 2019	Jan. 31, 2018
Revenues
Revenues	$ 1,607.9	$ 1,588.3
Operating profit (loss)
Income from unconsolidated affiliates, net	0.9	0.5
Operating profit (loss)	30.3	19.5
Interest expense	(13.5)	(14.3)
Income from continuing operations before income taxes	17.8	5.8
Operating Segments
Revenues
Revenues	1,642.3
Intersegment Eliminations
Revenues
Revenues	(34.4)	(38.9)
Corporate
Operating profit (loss)
Operating profit (loss)	(44.7)	(47.4)
Segment Reconciling Items
Operating profit (loss)
Income from unconsolidated affiliates, net	(0.9)	(0.6)
Adjustment for tax deductions for energy efficient government buildings, included in Technical Solutions	0.0	(0.3)
Business & Industry
Revenues
Revenues	774.5
Business & Industry \| Operating Segments
Revenues
Revenues	774.5	756.3
Operating profit (loss)
Operating profit (loss)	36.5	28.5
Aviation
Revenues
Revenues	252.4
Aviation \| Operating Segments
Revenues
Revenues	252.4	260.1
Operating profit (loss)
Operating profit (loss)	3.9	5.8
Technology & Manufacturing
Revenues
Revenues	236.1
Technology & Manufacturing \| Operating Segments
Revenues
Revenues	236.1	232.2
Operating profit (loss)
Operating profit (loss)	18.2	16.9
Education
Revenues
Revenues	204.7
Education \| Operating Segments
Revenues
Revenues	204.7	206.9
Operating profit (loss)
Operating profit (loss)	10.3	9.2
Technical Solutions
Revenues
Revenues	107.9
Technical Solutions \| Operating Segments
Revenues
Revenues	107.9	104.0
Operating profit (loss)
Operating profit (loss)	5.9	5.5
Healthcare
Revenues
Revenues	66.7
Healthcare \| Operating Segments
Revenues
Revenues	66.7	67.7
Operating profit (loss)
Operating profit (loss)	1.2	2.7
Government Services \| Operating Segments
Operating profit (loss)
Operating profit (loss)	$ 0.0	$ (0.7)

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