Stockholders' Equity - Stock Options Narrative (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]
Exercised (in shares)	4,225	12,157
Intrinsic value of options exercisable	$ 426
Options exercised, intrinsic value	$ 191
Stock price (in dollars per share)	$ 4.27
Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	10 years
Minimum \| Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
Maximum \| Stock option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting periods	10 years

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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Price of a single share of a number of saleable stocks of a company.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of share options (or share units) exercised during the current period.

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