Percent Of Executive Office Equity Awards Granted As Performance-Based Vesting Restricted Stock Units

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Percentage of the total number of shares of common stock outstanding on December 31 of the preceding calendar year which will be used as a basis for the annual automatic increase in the number of shares of common stock reserved for issuance under the 2013 Plan each year from January 1, 2014 through January 1, 2023.

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Term during which the number of shares of common stock reserved for issuance will automatically increase on January 1 each year.

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

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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.

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Amount of cost to be recognized for option under share-based payment arrangement.

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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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- Definition

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

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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

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

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

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Equity Incentive Plans and Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions		1 Months Ended	12 Months Ended
	Jan. 01, 2022	May 31, 2013	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of executive office equity awards granted as performance-based vesting restricted stock units			50.00%
Share-based Payment Arrangement, Tranche One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Share-based Payment Arrangement, Tranche Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			50.00%
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value (in dollars per share)					$ 4.51
Total fair value of stock options vested during period			$ 1.2	$ 1.5	$ 1.8
Options, compensation cost not yet recognized			$ 0.2
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			9 months 18 days
Aggregate intrinsic value of stock options exercised			$ 9.7	$ 2.3	$ 0.2
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			1 year 8 months 12 days
Nonvested RSUs, compensation cost not yet recognized			$ 7.4
Performance stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost related to nonvested awards, weighted-average period recognized			1 year 6 months
Nonvested RSUs, compensation cost not yet recognized			$ 2.3
Performance stock units \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			0.00%
Performance Shares, Two Thousand Twenty Fiscal Year Grants [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			150.00%
Performance Shares, Two Thousand Twenty One Fiscal Year Grants [Member] \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting rights percentage			200.00%
2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)		1,250,000
Common stock reserved for issuance increase, automatic increase, term		10 years
Number of shares reserved for issuance, automatic increase, percent of common stock outstanding of preceding calendar year (in shares)		5.00%
Number of shares available for future grant (in shares)			4,692,186
Subsequent Event \| 2013 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)	1,509,429