Accounts Receivable (Details) - USD ($)	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Receivables [Abstract]
Accounts Receivable Gross	$ 9,762,000	$ 8,717,000
Allowance for Doubtful Accounts	(964,000)	(859,000)	$ (524,000)
Accounts Receivable Net	$ 8,798,000	$ 7,858,000