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.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Stock-based Compensation (Narrative) (Details) $ / shares in Units, $ in Millions		1 Months Ended	12 Months Ended
	May 09, 2019	Nov. 30, 2020 shares	Dec. 31, 2020 USD ($) $ / shares shares
Reverse stock split ratio	0.0714		0.0714
Vesting percentage			100.00%
Vested			1,668,926
Assumed 2006 and 2016 Plan [Member]
Additional awards			0
Minimum [Member] \| Assumed 2006 and 2016 Plan [Member]
Expiration period of share-based payment award			2 years
Maximum [Member] \| Assumed 2006 and 2016 Plan [Member]
Expiration period of share-based payment award			4 years
Stock Option [Member]
Common stock closing price \| $ / shares			$ 2.98
Unrecognized compensation cost related to unvested options \| $			$ 3.4
Weighted-average remaining period for recognition of compensation costs related to unvested options			1 year 8 months 16 days
Restricted Stock Units (RSUs) [Member] \| New Employee [Member]
Granted (in shares)		70,000
Vested		33,000
Restricted Stock Units (RSUs) [Member] \| New Employee [Member] \| Share-based Payment Arrangement, Tranche One [Member]
Vesting period of share-based compensation award		6 months
Granted (in shares)		40,000
Restricted Stock Units (RSUs) [Member] \| New Employee [Member] \| Share-based Payment Arrangement, Tranche Two [Member]
Vesting period of share-based compensation award		3 years
Granted (in shares)		30,000
Equity Incentive Plan 2016 [Member]
Expiration period of share-based payment award			10 years
Vesting period of share-based compensation award			4 years