Stock Option Plans - Valuation Assumptions (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Stock options
Fair value assumptions
Stock-based compensation expense recognized in earnings	$ 0	$ 0	$ 0	$ 0

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

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