Stock-based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($) $ / shares shares
Stock Option [Member]
Common stock closing price \| $ / shares	$ 1.24
Unrecognized compensation cost related to unvested options \| $	$ 3.2
Restricted Stock Awards [Member]
Additional awards \| shares	0
Restricted Stock Awards [Member] \| Minimum [Member]
Vesting period of share-based compensation award	2 years
Restricted Stock Awards [Member] \| Maximum [Member]
Vesting period of share-based compensation award	4 years
Stock Options And Restricted Stock Awards [Member]
Weighted-average remaining period for recognition of compensation costs related to unvested options	1 year 9 months 18 days
Equity Incentive Plan 2016 [Member]
Vesting period of share-based compensation award	4 years
Equity Incentive Plan 2016 [Member] \| Maximum [Member]
Expiration period of share-based payment award	10 years

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
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Amount of cost to be recognized for option under share-based payment arrangement.

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-Publisher FASB
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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

+ References

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-Publisher FASB
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Number of shares issued under share-based payment arrangement.

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
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Price of a single share of a number of saleable stocks of a company.

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No definition available.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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