Product Warranties (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016
Product Warranties [Abstract]
Balance at beginning of period	$ 432,000	$ 650,000	$ 432,000	$ 650,000	$ 431,000	$ 431,000	$ 650,000	$ 650,000
Provision for warranties	71,000	102,000	154,000	216,000
Expenses incurred	$ (70,000)	$ (102,000)	$ (153,000)	$ (216,000)