Notes Payable - Related Party (Narrative) (Details) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020
Notes Payable [Abstract]
Interest expense	$ 52,000	$ 86,000	$ 104,000	$ 146,000
Interest payable	$ 0		$ 0		$ 0

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration