Accounts Payable and Accrued Expenses - Schedule of Product Warranty Liability (Details) - USD ($)	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Payables and Accruals [Abstract]
Accrued warranty reserve, beginning of year	$ 422,000	$ 535,000
Accrual for product warranties issued	80,000	23,000
Product replacements and other warranty expenditures	(54,000)	(33,000)
Expiration of warranties	(76,000)	(30,000)
Accrued warranty reserve, end of period	$ 372,000	$ 495,000