Summary of Significant Accounting Policies (Narrative) (Details) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($) segment	Jun. 30, 2022 USD ($)	Dec. 31, 2021 USD ($) contract $ / shares	Mar. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Mar. 31, 2022 USD ($)	Sep. 30, 2021 USD ($)
Summary of Significant Accounting Policies [Line Items]
Equipment on operating leases, depreciation method			straight-line method
Investment in equity securities	$ 19		$ 19				$ 21
Unrealized loss on fair value adjustment for equity securities	6	$ 72	$ 2	$ 256
Investment in short options, initial									$ 50
Options, short position, contract expiration date			Jan. 21, 2022
Number of operating segments | segment			1
Number of reportable segments | segment			1
Unrealized gain (loss) on fair value adjustment for warrants		1	$ (2)	2
Warrants, fair value	$ 136	$ 144	136	144	$ 142	$ 136	$ 138	$ 143
Realized gain on sale of options				$ 1
Short Position Options Sold - Tranche One [Member]
Summary of Significant Accounting Policies [Line Items]
Short position options, number of contracts sold | contract					125
Short position options contracts sold, premium per share | $ / shares					$ 3.00
Options, short position, strike price per share | $ / shares					$ 15.00
Short Position Options Sold - Tranche Two [Member]
Summary of Significant Accounting Policies [Line Items]
Short position options, number of contracts sold | contract					75
Short position options contracts sold, premium per share | $ / shares					$ 1.64
Options, short position, strike price per share | $ / shares					$ 12.50
Minimum [Member]
Summary of Significant Accounting Policies [Line Items]
Required assets value of financial institutions for cash deposits			$ 10,000,000
Operating leases, initial terms	36 months		36 months
Maximum [Member]
Summary of Significant Accounting Policies [Line Items]
Treasury instruments maturity period			90 days
Cash deposits, insured amount	$ 250		$ 250
Operating leases, initial terms	120 months		120 months