Number of days after the annual meeting stockholder meeting that the board compensation will be granted.

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The performance target payout over the life of the performance period for performance based awards granted as a percentage of the target amount.

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The period over which performance is evaluated against a target.

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- Definition

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

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- Definition

Description of the deferred compensation arrangement, including fixed amounts and determinable awards, or the method for determining payments and awards, the timing of such payments and awards, and any requisite service or performance criteria, as of the balance sheet date.

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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 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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Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance.

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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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No definition available.

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- Definition

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

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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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- 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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Share-based Compensation - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Exercise period of options	10 years
Non-Employee Directors [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Non-employee director compensation grant period	5 days
Maximum [Member] \| Graded and Cliff Vesting [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of options	5 years
2015 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares available for grant	1,100,000
Long Term Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance target for achievement period	3 years
Long Term Incentive Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of performance target for achievement	0.00%
Long Term Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of performance target for achievement	150.00%
Stock Compensation Plans [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense	$ 7.4	$ 5.6	$ 5.1
Unrecognized share-based compensation expense	$ 10.1
Period of recognition of share-based compensation expense	1 year 9 months 18 days
Stock Compensation Plans [Member] \| 2015 Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Maximum aggregate number of shares	2,600,000
Number of additional shares,Maximum aggregate number of shares	1,050,000.00
Shares available for grant	900,000
Plan description	As of December 31, 2021, subject to adjustments as provided in the 2015 Plan, the maximum aggregate number of shares of the Company’s common stock that could be issued under the 2015 Plan could not exceed the sum of (i) 2.6 million shares (such amount reflecting an increase of 1.05 million additional or “new” shares in connection with the May 20, 2021 re-approval of the 2015 Plan) plus (ii) any shares remaining available for the grant of awards as of the 2015 Plan effective date (April 22, 2015) under the 2007 Plan or the 2011 Plan, plus (iii) any shares subject to an award granted under the 2007 Plan or the 2011 Plan, which award is forfeited, cash-settled, cancelled, terminated, expires, or lapses for any reason without the issuance of shares or pursuant to which such shares are forfeited. As of the effectiveness of the 2015 Plan (April 22, 2015), there were 0.9 million shares available for grant under the 2015 Plan, inclusive of shares previously available for grant under the 2007 Plan and the 2011 Plan that were rolled over to the 2015 Plan
Restricted Stock [Member] \| Key Team Member Incentive Plan [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Performance target for achievement period	1 year
Vesting period of options	2 years
Deferred compensation arrangement with individual, description	Each participant in the program is eligible to earn an RSA, subject to performance over a one-year period. Payout under the program can range from 0% to 150% of target based on the achievement of five Company performance metrics and individual performance goals (subject to continued employment and certain other terms and conditions of the program).
Restricted Stock [Member] \| Key Team Member Incentive Plan [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of performance target for achievement	0.00%
Restricted Stock [Member] \| Key Team Member Incentive Plan [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of performance target for achievement	150.00%