Fair Value Measurements (Estimated Fair Values of Financial Instruments) (Details) - USD ($)	Sep. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Sep. 30, 2021	Jun. 30, 2021	Dec. 31, 2020
Financial assets:
Cash and cash equivalents	$ 902,000		$ 1,748,000
Investment in equity securities	3,000		8,000
Warrants, fair value	0		3,000
Financial liabilities:
Non-recourse debt	1,411,000		2,197,000
Level 1 Estimated Fair Value [Member]
Financial assets:
Cash and cash equivalents	902,000		1,748,000
Investment in equity securities	3,000	$ 3,000	8,000	$ 9,000	$ 12,000	$ 238,000
Warrants, fair value			0
Financial liabilities:
Non-recourse debt	0		0
Level 2 Estimated Fair Value [Member]
Financial assets:
Cash and cash equivalents	0		0
Investment in equity securities	0		0
Warrants, fair value			0
Financial liabilities:
Non-recourse debt	0		0
Level 3 Estimated Fair Value [Member]
Financial assets:
Cash and cash equivalents	0		0
Investment in equity securities	0		0
Warrants, fair value			3,000	$ 3,000	$ 3,000	$ 31,000
Financial liabilities:
Non-recourse debt	1,411,000		2,197,000
Carrying Amount [Member]
Financial assets:
Cash and cash equivalents	902,000		1,748,000
Investment in equity securities	3,000		8,000
Warrants, fair value			3,000
Financial liabilities:
Non-recourse debt	$ 1,432,000		$ 2,163,000