Share based compensation arrangement by share based payment award number of installments.

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- Definition

Share based compensation arrangement by share based payment award percentage of performance conditions need to be met in order for the shares to vest.

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Share based compensation arrangement by share based payment award performance condition.

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- Definition

Share-based compensation arrangement by share-based payment award, share price to be increased before vesting period..

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- Definition

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

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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.

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- Definition

Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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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

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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.

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- Definition

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

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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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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

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

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No definition available.

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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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- Definition

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

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- Definition

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

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- Definition

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

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Equity-Based Compensation - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Weighted-average fair value on the date of grant of stock options granted	$ 3.46	$ 1.77	$ 1.26
Stock-based compensation expense for non-vested equity-based compensation	$ 3,100
Stock based compensation expense, recognition period	27 months
Options exercised (in shares)	65,300	0	80,000
Intrinsic value of shares exercised	$ 300	$ 100	$ 100
Increase in stock price	$ 9.97
Share-based Payment Arrangement, Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	0
Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Dividends paid	$ 0	$ 0	$ 0
Restricted Stock [Member] \| Stock Vesting, One Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage	33.00%	33.00%	33.00%
Restricted Stock [Member] \| Stock Vesting, Two Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage	25.00%	25.00%	25.00%
Restricted Stock [Member] \| Stock Vesting, Three Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage	33.00%	33.00%	33.00%
Restricted Stock [Member] \| Stock Vesting, Four Year From Grant Date [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares vesting percentage	25.00%	25.00%	25.00%
Minimum [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years
Maximum [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	4 years
2010 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant		0
Stock options granted		173,010	26,500
Options exercised (in shares)	45,096	45,096	45,096
Intrinsic value of shares exercised	$ 100	$ 0	$ 100
2010 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted		599,928	636,268
Number of shares, cancelled	147,008	129,878	228,151
Number of shares, outstanding	929,745	1,484,985	1,146,884	850,927
Restricted stock and stock units, granted		599,928	636,268
Number of shares, cancelled	147,008	129,878	228,151
Number of shares, outstanding	929,745	1,484,985	1,146,884	850,927
2010 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	3 years
Award vesting period	1 year
2010 Equity Award Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	4 years
Award vesting period	15 years
2020 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant	1,581,616
Number of shares authorized	1,950,000
Stock options granted	105,906
2020 Equity Award Plan [Member] \| Share-based Payment Arrangement, Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted	105,906
2020 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Restricted stock and stock units, granted	267,036
Number of shares, cancelled	4,558
Number of shares, outstanding	250,566
Restricted stock and stock units, granted	267,036
Number of shares, cancelled	4,558
Number of shares, outstanding	250,566
2020 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	3 years
Award vesting period	1 year
2020 Equity Award Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	4 years
Award vesting period	15 years
2000 Equity Award Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant	0
Expiration period	9 years 6 months
Options exercised (in shares)	65,300		80,000
2000 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares, outstanding		40,000	40,000	40,000
Number of shares, outstanding		40,000	40,000	40,000
2000 Equity Award Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	3 years
Award vesting period	1 year
2000 Equity Award Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Years of annual installments in which stock options become exercisable	4 years
Expiration period	15 years
1991 Equity Award Plan [Member] \| Restricted Stock [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of shares available for grant	20,116
Number of shares authorized	800,000
Number of shares, cancelled	250	1,925	10,874
Number of shares, outstanding		10,980	24,375	56,117
Number of shares, cancelled	250	1,925	10,874
Number of shares, outstanding		10,980	24,375	56,117
2010 Equity Award Plan [Member] \| Share-based Payment Arrangement, Option
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock options granted		173,010	26,500
2010 Equity Award Plan [Member] \| Performance Shares [Member] \| Senior Management [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Award vesting period	3 years	3 years	3 years
Weighted-average fair value on the date of grant of stock options granted	$ 9.17	$ 5.88	$ 4.93
Shares vesting percentage	100.00%	100.00%	100.00%
Restricted stock and stock units, granted	79,917	115,410	217,542
Performance conditions	Under these grant agreements, the Company’s cumulative three-year non-GAAP earnings per share for the years 2021, 2022, and 2023 must equal or exceed $2.01 for 100% of the grants to vest. If the combined cumulative three-year non-GAAP earnings per share is 80% or more but less than 100% of the earnings per share target, a pro-rata portion of the grants shall vest. If at least 80% of the three-year non-GAAP earnings per share target is not met, the grants will expire.	Under these grant agreements, the Company’s cumulative three-year non-GAAP earnings per share for the years 2020, 2021, and 2022 must equal or exceed $1.77 for 100% of the grants to vest. If the combined cumulative three-year non-GAAP earnings per share is 80% or more but less than 100% of the earnings per share target, a pro-rata portion of the grants shall vest. If at least 80% of the three-year non-GAAP earnings per share target is not met, the grants will expire.	Under these grant agreements, the Company’s cumulative three-year non-GAAP earnings per share for the years 2019, 2020, and 2021 must equal or exceed $1.42 for 100% of the grants to vest. If the combined cumulative three-year non-GAAP earnings per share is 80% or more but less than 100% of the earnings per share target, a pro-rata portion of the grants shall vest. If at least 80% of the three-year non-GAAP earnings per share target is not met, the grants will expire
Increase in stock price	$ 2.01	$ 1.77	$ 1.42
Percentage of shares to be increased before vesting period	80.00%	80.00%	80.00%
Fair value of performance share units	$ 700	$ 700	$ 1,100
Number of shares, cancelled	0	0
Number of shares, outstanding	79,917	115,410	217,542
Restricted stock and stock units, granted	79,917	115,410	217,542
Number of shares, cancelled	0	0
Number of shares, outstanding	79,917	115,410	217,542