Product Warranties (Tables)

6 Months Ended

Mar. 31, 2017

Product Warranties [Abstract]

Schedule of Product Warranty Liability [Table Text Block]

Changes in the Company's warranty liability (included in accrued expenses) for the three and six month periods ended March 31, 2017 and 2016 were as follows:

	Three Months Ended March 31,						Six Months Ended March 31,
	2017			2016			2017			2016
Balance at beginning of period	$	650,000		$	650,000		$	650,000		$	650,000
Provision for warranties	102,000			110,000			216,000			218,000
Expenses incurred	(102,000		)	(110,000		)	(216,000		)	(218,000		)
Balance at end of period	$	650,000		$	650,000		$	650,000		$	650,000