Investment in Joint Venture (Narrative) (Details) - USD ($)	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Dec. 31, 2015
Investment in Joint Venture [Abstract]
Investment in joint venture	$ 889,000		$ 891,000	$ 900,000
Income (loss) from joint venture investment	$ (6,000)	$ 0

Amount of income (loss) for proportionate share of equity method investee's income (loss).

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