Summary of Significant Accounting Policies - Warranty (Details) - USD ($) $ in Thousands	9 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Warranty beginning balance	$ 795	$ 793
Additions for warranties issued during the period	899	691
Reductions for payments made under the warranty	(269)	(624)
Changes related to pre-existing warranties	(582)	(121)
Currency translation adjustment	10	6
Warranty ending balance	$ 853	$ 745
Minimum
Product Warranty Liability [Line Items]
Standard product warranty, period	12 months
Maximum
Product Warranty Liability [Line Items]
Standard product warranty, period	24 months