Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Cash paid for:
Interest	$ 39	$ 26	$ 286
Income taxes			638
Noncash investing and financing activities:
Inventory transferred to rental equipment	1,677	3,982	5,013
Inventory transferred to property, plant and equipment	1,863	$ 130	98
Financing receivables in connection with sale of used rental equipment	$ 9,386
Settlement of note receivable in connection with return of rental equipment			2,588
Prepaid assets transferred to property, plant and equipment			$ 4,219