Segment Information - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018
Unallocated corporate expenses and other
Segment Information
Expense related to strategic and IT system resource planning	$ 2.3	$ 5.7	$ 3.9	$ 13.7

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.

No definition available.

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