Segment Information - Narrative (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Unallocated corporate expenses
Segment Information
Expense related to strategic and IT system resource planning	$ 0.3	$ 2.4	$ 3.3	$ 6.3

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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