Stock-based Compensation - Summary of Status and Activity of Non-Vested Stock Awards (Detail)	12 Months Ended
Dec. 31, 2020 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested, Beginning Balance	788,198
Granted	601,642
Performance share adjustment	(150,464)
Vested	(278,702)
Forfeited	(59,421)
Non-vested, Ending Balance	901,253
Beginning Balance, Non-vested, Weighted Average Grant Date Fair Value per Unit \| $ / shares	$ 40.18
Granted, Weighted Average Grant Date Fair Value per Unit \| $ / shares	15.86
Performance share adjustment, Weighted Average Grant Date Fair Value per Unit \| $ / shares	30.68
Vested, Weighted Average Grant Date Fair Value per Unit \| $ / shares	41.68
Forfeited, Weighted Average Grant Date Fair Value per Unit \| $ / shares	33.86
Ending Balance, Non-vested, Weighted Average Grant Date Fair Value per Unit \| $ / shares	$ 25.48
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested, Beginning Balance	343,012
Granted	369,161
Performance share adjustment	0
Vested	(168,534)
Forfeited	(34,130)
Non-vested, Ending Balance	509,509
Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Non-vested, Beginning Balance	445,186
Granted	232,481
Performance share adjustment	(150,464)
Vested	(110,168)
Forfeited	(25,291)
Non-vested, Ending Balance	391,744

Share based compensation arrangement by performance share adjustment.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options performance share adjustment.

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Publisher FASB
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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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-Publisher FASB
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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-Publisher FASB
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- Definition

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

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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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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