Stock-Based Compensation - Service Based Stock Options - Others (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expenses	$ (179)	$ (236)
Stock option awards - service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	909	7,672
Forfeited (in shares)	14,839	16,721
Expirations (in shares)	3,545	20,530
Stock based compensation expenses	$ 200	$ 391
Unrecognized stock-based compensation expenses	$ 1,000
Unrecognized stock-based compensation expense, weighted average remaining term (in years)	3 years 1 month 6 days

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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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Amount of cost to be recognized for option under share-based payment arrangement.

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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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