Acquisitions - Schedule of Consolidated Pro Forma Financial Information (Details) - Nexeo Solutions Inc. - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Business Acquisition [Line Items]
Sales and operating revenues	$ 1,046.4	$ 942.7	$ 3,017.0	$ 2,690.4
Operating income	40.1	26.1	97.9	38.4
Net income from continuing operations	17.5	11.7	44.4	3.1
Net income	$ 17.5	$ 11.7	$ 44.4	$ 3.1
Basic net income per share (USD per share)	$ 0.23	$ 0.15	$ 0.58	$ 0.04
Diluted net income per share (USD per share)	$ 0.23	$ 0.15	$ 0.58	$ 0.04
Pro forma 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

Business Acquisition, Pro Forma Operating Income (Loss)

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

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The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

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