Inventories - Narrative (Details) - USD ($) $ in Millions	Jun. 30, 2019	Sep. 30, 2018
Inventory Disclosure [Abstract]
Finished goods inventory that has been shipped, but for which all revenue recognition criteria has not been met	$ 0.8	$ 0.7
Reserve for obsolescence	$ 3.7	$ 3.3

Amount of valuation reserve for inventory.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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Name:	us-gaap_InventoryValuationReserves
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant