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.

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No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

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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).

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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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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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		3 Months Ended		6 Months Ended
	May 16, 2019	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Authorizes issuance of common stock		4,350,000		4,350,000
Number of shares available for grant		1,500,000		1,500,000
Maximum shares that may be used as full value awards				1,200,000
Stock-based compensation expense		$ 1.4	$ 1.0	$ 1.9	$ 1.7
Amount of unrecognized stock-based compensation expense		$ 11.7		$ 11.7
Weighted average period for recognition				2 years 1 month 6 days
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period				3 years
Grants in period				905,089
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				1,475,277
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% 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