Percentage of benefit received by employees is equal to discount on the shares of common stock purchased.

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- Definition

Share-based Compensation Arrangement By Share-Based Payment Award, Maximum Number Of Shares Per Employee, Value

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No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage Of Employee's Annual Cash Compensation

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Plan Term

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No definition available.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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- Definition

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

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- Definition

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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- Definition

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.

+ References

No definition available.

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- Definition

Number of shares authorized for issuance under share-based payment arrangement.

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-Publisher FASB
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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- Definition

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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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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-Publisher FASB
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- Definition

Percentage of vesting of award under share-based payment arrangement.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Equity Incentive Plans - Narrative (Details) - USD ($)	1 Months Ended		12 Months Ended
Equity Incentive Plans - Narrative (Details) - USD ($)	Jul. 31, 2018	Sep. 30, 2013	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Intrinsic value of stock options exercised			$ 100,000	$ 100,000
Total fair value of equity awards vested			$ 5,000,000.0	$ 8,400,000
Weighted-average grant date fair values of stock options granted (in dollars per share)			$ 3.47	$ 3.48
Share-based compensation expense			$ 4,477,000	$ 6,207,000
Unamortized share-based compensation expense			$ 7,100,000
Recognized weighted average period			2 years 10 months 24 days
2013 Equity Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity plan, term		10 years
Period of share-based payment awards		4 years
Number of shares reserved for issuance			9,600,000
Shares available for grant (in shares)			5,503,796	5,478,334
2013 Equity Plan [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Period of share-based payment awards		1 year
2013 Equity Plan [Member] \| One-year Anniversary Date of Grant [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights, percentage		25.00%
2018 Employee Stock Purchase Plan [Member] \| Share-based Payment Arrangement, Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance	750,000
Shares available for grant (in shares)			335,473	455,768
Percent of employee's annual cash compensation	85.00%
Maximum number of shares per employee	$ 25,000
Percentage of benefit received by employees is equal to discount on the shares of common stock purchased	15.00%
Share-based compensation expense			$ 100,000	$ 100,000
Unrecognized share-based compensation expense			$ 0