Recent Accounting Pronouncements - Narrative (Details) $ in Millions	6 Months Ended
Mar. 31, 2018 USD ($)
Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI to retaIned earnings due to TCJA	$ 11.7
Accumulated other comprehensive loss, net of tax
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Reclassification from AOCI to retaIned earnings due to TCJA	$ (11.7)

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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