Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Sales and operating revenues	$ 1,046.4	$ 942.7	$ 3,017.0	$ 2,655.2
Cost of sales and operating expenses	926.2	840.0	2,674.2	2,365.9
Gross profit	120.2	102.7	342.8	289.3
Selling, general and administrative expenses	88.8	79.4	259.5	233.9
Transaction related costs	0.0	0.2	0.1	1.3
Change in fair value of contingent consideration obligations	(8.7)	(0.8)	(14.7)	19.8
Operating income	40.1	23.9	97.9	34.3
Other income, net	0.4	5.7	0.9	8.3
Interest income (expense)
Interest income	0.2	0.0	0.4	0.2
Interest expense	(13.5)	(13.5)	(39.2)	(38.0)
Net income before income taxes	27.2	16.1	60.0	4.8
Income tax expense	9.7	5.9	15.6	4.0
Net income attributable to Nexeo Solutions, Inc.	$ 17.5	$ 10.2	$ 44.4	$ 0.8
Net income per share available to common stockholders
Basic (USD per share)	$ 0.23	$ 0.13	$ 0.58	$ 0.01
Diluted (USD per share)	$ 0.23	$ 0.13	$ 0.58	$ 0.01
Weighted average number of common shares outstanding
Basic (in shares)	76,797,414	76,743,853	76,795,551	76,745,396
Diluted (in shares)	76,983,350	76,828,868	76,952,758	76,830,296