Stock-Based Compensation - Service Based Stock Options - Others (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expenses	$ 943	$ 475
Stock option awards - Service based awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	1,947,162	2,288,386
Vested options, exercisable (in shares)	2,612,079
Vested options exercisable at an average price (in dollars per share)	$ 4.81
Stock based compensation expenses	$ 1,354	$ 1,491
Unvested options (in shares)	3,202,427
Unrecognized stock-based compensation expenses	$ 1,300
Period of recognition for unrecognized stock-based compensation expenses	3 years 1 month 6 days

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

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

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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

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