Minimum percentage of fair market value on the date of grant used to establish stock option exercise price.

No definition available.

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- Definition

The percentage of the annual share based payment award delivered in the form of shares of restricted stock, performance stock units or stock options.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award settlement.

+ References

No definition available.

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- Definition

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

+ References

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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 cash outflow to satisfy grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3291-108585

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- Definition

Amount of cash inflow from exercise of option under share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2A
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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.

+ References

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- Definition

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).

+ References

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- Definition

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

+ References

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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

The highest quantity of shares an employee can purchase under the plan per period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

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

+ References

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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.

+ References

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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.

+ References

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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.

+ References

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- Definition

Number of shares used to settle grantee's tax withholding obligation for award under share-based payment arrangement.

+ References

No definition available.

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- Definition

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

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Share Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from the issuance of stock options		$ 1,814	$ 4,405	$ 474
Shares withheld to meet employees' minimum statutory income tax obligation		425,000	409,000	211,000
Payments for the employees' minimum statutory income tax obligation		$ 1,367	$ 1,131	$ 543
Board of Directors [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares vested with deferral		72
Employees Tax Obligations [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Payments for the employees' minimum statutory income tax obligation		$ 1,367	$ 1,131	$ 543
Amended and Restated Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation arrangement by share-based payment award, number of shares authorized		40,200,000
Maximum number of shares of stock granted to one participant		4,000,000
Minimum percentage of exercise price		100.00%
Shares available for grant under the plan		3,742,000
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Per share weighted average fair value of options granted		$ 1.42	$ 1.54	$ 1.45
Proceeds from the issuance of stock options		$ 1,814	$ 4,405	$ 474
Exercise of options, shares		939,000	2,529,000	447,000
Shares withheld to meet employees' minimum statutory income tax obligation		43,000	30,000
Unrecognized compensation cost related to non-vested outstanding stock awards		$ 5,273
Weighted average period expected to be recognized		1 year 11 months 23 days
Stock Options [Member] \| Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term of options granted		10 years
Vesting period		3 years
Stock Options [Member] \| Amended and Restated Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term of options granted		10 years
Vesting period		3 years
Stock Options [Member] \| Minimum [Member] \| Amended and Restated Equity Compensation Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		1 year
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in 2017		1,078,000	789,000	611,000
Number of shares vested with deferral		785,000	614,000	500,000
Restricted Stock Units [Member] \| Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted in 2017		605,000	593,000	611,000
Number of shares vested with deferral		388,000	415,000	173,000
Performance Stock Units [Member] \| Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Number of shares granted in 2017		556,000
Performance Stock Units [Member] \| Long Term Incentive Program [Member] \| Scenario, Forecast [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares approved for settlement	766,000
Performance Stock Units [Member] \| Minimum [Member] \| Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation award percentage		0.00%
Performance Stock Units [Member] \| Maximum [Member] \| Long Term Incentive Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation award percentage		150.00%