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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Loss Carryforwards [Line Items]
U.S. federal statutory income tax rate	21.00%	21.00%	21.00%
Operating loss carryforwards indefinitely	$ 11,042,000
Operating loss carryforwards, limitations on use	The Company also has indefinite life carryforwards as a result of interest limitations. Starting in 2022, the Company has research costs attributable to research and development that are currently expensed but are required to be capitalized for U.S. tax purposes and amortized primarily over 5 or 15 years.
Interest and penalties recorded	$ 0	$ 0	$ 0
Deferred tax assets valuation allowance	6,012,000	2,487,000
Domestic Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	54,376,000	55,554,000
Operating loss carryforwards expiration amount	$ 43,334,000
Operating loss carryforwards expiration year	2037
Deferred tax assets valuation allowance	$ 0	0
State and Local Jurisdiction [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	188,884,000	157,245,000
Valuation allowance for net operating loss carryforwards	$ 5,988,000	1,623,000
State and Local Jurisdiction [Member] | Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2027
State and Local Jurisdiction [Member] | Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2042
Foreign Tax Authority [Member]
Operating Loss Carryforwards [Line Items]
Loss carryforwards for federal income tax purposes	$ 69,000	2,469,000
Valuation allowance for net operating loss carryforwards	$ 24,000	$ 864,000
Foreign Tax Authority [Member] | Minimum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2023
Foreign Tax Authority [Member] | Maximum [Member]
Operating Loss Carryforwards [Line Items]
Operating loss carryforwards expiration year	2028

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-Name Accounting Standards Codification
-Topic 740
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