Receivables, net - Additional Information (Details) - Credit Concentration Risk [Member]	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Accounts, Notes, Loans and Financing Receivable [Line Items]
Percentage of net sales from major customer	15.10%	15.20%	14.70%
Percentage Of Accounts Receivable Major Customers	14.00%	15.10%

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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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration