Equity-Based Compensation - Schedule of Employee Stock Performance Activity (Detail)	12 Months Ended
Dec. 31, 2020 $ / shares shares
Time-Vesting Restricted Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares/Units, Outstanding, Beginning Balance \| shares	725,911
Shares/Units, Granted \| shares	1,476,758
Shares/Units, Vested \| shares	(432,497)
Shares/Units, Forfeited \| shares	(77,593)
Shares/Units, Outstanding, Ending Balance \| shares	1,692,579
Weighted Average Grant Date Fair Value per Award, Outstanding, Beginning Balance \| $ / shares	$ 21.08
Weighted Average Grant Date Fair Value per Award, Granted \| $ / shares	12.99
Weighted Average Grant Date Fair Value per Award, Vested \| $ / shares	20.18
Weighted Average Grant Date Fair Value per Award, Forfeited \| $ / shares	22.71
Weighted Average Grant Date Fair Value per Award, Outstanding, Ending Balance \| $ / shares	$ 14.18
Bonus Performance Restricted Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares/Units, Outstanding, Beginning Balance \| shares	333,673
Shares/Units, Vested \| shares	(97,616)
Shares/Units, Forfeited \| shares	(212,759)
Shares/Units, Outstanding, Ending Balance \| shares	23,298
Weighted Average Grant Date Fair Value per Award, Outstanding, Beginning Balance \| $ / shares	$ 26.10
Weighted Average Grant Date Fair Value per Award, Vested \| $ / shares	26.11
Weighted Average Grant Date Fair Value per Award, Forfeited \| $ / shares	26.09
Weighted Average Grant Date Fair Value per Award, Outstanding, Ending Balance \| $ / shares	$ 26.16
Long-Term Incentive Performance Restricted Awards [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares/Units, Outstanding, Beginning Balance \| shares	1,855,828
Shares/Units, Granted \| shares	246,374
Shares/Units, Vested \| shares	(79,173)
Shares/Units, Forfeited \| shares	(555,393)
Shares/Units, Outstanding, Ending Balance \| shares	1,467,636
Weighted Average Grant Date Fair Value per Award, Outstanding, Beginning Balance \| $ / shares	$ 22.34
Weighted Average Grant Date Fair Value per Award, Granted \| $ / shares	33.23
Weighted Average Grant Date Fair Value per Award, Vested \| $ / shares	17.55
Weighted Average Grant Date Fair Value per Award, Forfeited \| $ / shares	25.11
Weighted Average Grant Date Fair Value per Award, Outstanding, Ending Balance \| $ / shares	$ 23.38

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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

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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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