Stock-Based Compensation - Summary of Stock-based Compensation Stock Options Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022	Dec. 31, 2021
2005 Plan
Stock Option Activity
Number of options outstanding, Beginning of period (in shares)	52,000
Number of options outstanding, Granted (in shares)	0
Number of options outstanding, Exercised (in shares)	0
Number of options outstanding, Forfeited (in shares)	0
Number of options outstanding, Expired (in shares)	0
Number of options outstanding, Ending of period (in shares)	52,000	52,000
Weighted Average Exercise Price
Weighted average exercise price, Outstanding beginning (USD per share)	$ 6.37
Weighted average exercise price, Granted (USD per share)	0
Weighted average exercise price, Exercised (USD per share)	0
Weighted average exercise price, Forfeited (USD per share)	0
Weighted average exercise price, Expired (USD per share)	0
Weighted average exercise price, Outstanding ending (USD per share)	$ 6.37	$ 6.37
Stock Option Additional Disclosures
Number of options outstanding, Full vested and expected to vest (in shares)	52,000
Number of options outstanding, Vested (in shares)	52,000
Weighted average exercise price, Full vested and expected to vest (USD per share)	$ 6.37
Weighted average exercise price, Vested (USD per share)	$ 6.37
Aggregate intrinsic value, Outstanding	$ 389	$ 333
Aggregate intrinsic value, Fully vested and expected to vest	389
Aggregate intrinsic value, Vested	$ 389
2010 Plan
Stock Option Activity
Number of options outstanding, Beginning of period (in shares)	210,000
Number of options outstanding, Granted (in shares)	0
Number of options outstanding, Exercised (in shares)	0
Number of options outstanding, Forfeited (in shares)	0
Number of options outstanding, Expired (in shares)	0
Number of options outstanding, Ending of period (in shares)	210,000	210,000
Weighted Average Exercise Price
Weighted average exercise price, Outstanding beginning (USD per share)	$ 8.00
Weighted average exercise price, Granted (USD per share)	0
Weighted average exercise price, Exercised (USD per share)	0
Weighted average exercise price, Forfeited (USD per share)	0
Weighted average exercise price, Expired (USD per share)	0
Weighted average exercise price, Outstanding ending (USD per share)	$ 8.00	$ 8.00
Stock Option Additional Disclosures
Number of options outstanding, Full vested and expected to vest (in shares)	210,000
Number of options outstanding, Vested (in shares)	210,000
Weighted average exercise price, Full vested and expected to vest (USD per share)	$ 8.00
Weighted average exercise price, Vested (USD per share)	$ 8.00
Aggregate intrinsic value, Outstanding	$ 1,229	$ 1,000
Aggregate intrinsic value, Fully vested and expected to vest	1,229
Aggregate intrinsic value, Vested	$ 1,229

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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