Supplemental Cash Flow Information (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2013
Cash paid for:
Interest	$ 286	$ 438	$ 119
Income taxes	638	15,163	29,837
Noncash investing and financing activities:
Inventory transferred to rental equipment	5,013	$ 10,742	$ 4,902
Inventory transferred to property, plant and equipment	98
Settlement of note receivable in connection with return of rental equipment	2,588
Prepaid assets transferred to property, plant and equipment	$ 4,219