Notes Payable - Related Party (Narrative) (Details) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020	Dec. 31, 2020
Notes Payable [Abstract]
Interest expense	$ 52,000	$ 74,000	$ 156,000	$ 220,000
Interest payable	$ 0		$ 0		$ 0

Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration