Full value awards maximum number of shares authorized under plan.

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- Definition

Sharebased compensation arrangement by sharebased payment award earned up on target percentage.

+ References

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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- 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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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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Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition.

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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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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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No definition available.

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

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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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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions		12 Months Ended
	May 16, 2019	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorizes issuance of common stock		4,350,000
Number of shares available for grant		200,000
Maximum shares that may be used as full value awards		1,200,000
Stock-based compensation expense		$ 2.4	$ 5.7
Amount of unrecognized stock-based compensation expense		$ 3.3
Weighted average period for recognition		1 year 6 months
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Grants in period		763,674
Restricted Stock Units [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period	333,333
Performance Shares Unit [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years
Grants in period		1,207,351
PSU awards earnings expected target	200.00%
Performance Shares Unit [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Grants in period	666,667
Shares awarded under the plan, vesting description		(a) 666,667 PSUs at target, vesting in three approximately equal installments, to the extent the performance metrics are satisfied, during each of three performance periods and (b) 333,333 RSUs, vesting in approximately equal installments on February 28, 2020, 2021 and 2022; (ii) a 2019-2021 PSU grant, with the target number of 316,832 PSUs, which will vest to the extent the performance metrics are satisfied; and (iii) a 2019 RSU grant of 158,416 RSUs, vesting in approximately equal installments on February 28, 2020, 2021 and 2022. The PSU awards may be earned at up to 200 percent of target depending on the level of achievement of the performance metrics
2019-2021 PSU [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period	316,832
2019 RSU [Member] \| President and Chief Executive Officer [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period	158,416