Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2017
Concentration Risk [Line Items]
Inventories	$ 1,247		$ 454
Revenue from acquisitions	17,052
Net income from acquisitions	$ 3,285
Product Concentration Risk \| Gross Revenue
Concentration Risk [Line Items]
Discount fees as percent of gross revenue (percent)	85.00%	85.00%

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

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