Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Cash paid for:
Interest	$ 26	$ 286	$ 438
Income taxes		638	15,163
Noncash investing and financing activities:
Inventory transferred to rental equipment	3,982	5,013	$ 10,742
Inventory transferred to property, plant and equipment	$ 130	98
Settlement of note receivable in connection with return of rental equipment		2,588
Prepaid assets transferred to property, plant and equipment		$ 4,219