Shared-Based Compensation - Reconciliation of Restricted Stock Option Activity (Detail)	9 Months Ended
Sep. 30, 2020 $ / shares shares
Restricted stock
Nonvested Shares (in thousands)
Nonvested restricted shares, beginning balance (in shares) \| shares	222,000
Nonvested restricted shares, granted (in shares) \| shares	460,255
Nonvested restricted shares, vested (in shares) \| shares	(145,000)
Nonvested restricted shares, forfeited (in shares) \| shares	(18,000)
Nonvested restricted shares, ending balance (in shares) \| shares	519,000
Weighted Average Grant-Date Fair Value (per share)
Beginning balance (in dollars per share) \| $ / shares	$ 9.33
Granted (in dollars per share) \| $ / shares	9.35
Vested (in dollars per share) \| $ / shares	8.61
Forfeited (in dollars per share) \| $ / shares	9.32
Ending balance (in dollars per share) \| $ / shares	$ 9.28
TSR Awards
Nonvested Shares (in thousands)
Nonvested restricted shares, beginning balance (in shares) \| shares	65,000
Nonvested restricted shares, granted (in shares) \| shares	139,000
Nonvested restricted shares, forfeited (in shares) \| shares	(19,000)
Nonvested restricted shares, ending balance (in shares) \| shares	185,000
Weighted Average Grant-Date Fair Value (per share)
Beginning balance (in dollars per share) \| $ / shares	$ 13.27
Granted (in dollars per share) \| $ / shares	10.88
Forfeited (in dollars per share) \| $ / shares	11.43
Ending balance (in dollars per share) \| $ / shares	$ 11.55
ROIC Awards
Nonvested Shares (in thousands)
Nonvested restricted shares, beginning balance (in shares) \| shares	79,000
Nonvested restricted shares, granted (in shares) \| shares	157,000
Nonvested restricted shares, forfeited (in shares) \| shares	(21,000)
Nonvested restricted shares, ending balance (in shares) \| shares	215,000
Weighted Average Grant-Date Fair Value (per share)
Beginning balance (in dollars per share) \| $ / shares	$ 11.50
Granted (in dollars per share) \| $ / shares	9.44
Forfeited (in dollars per share) \| $ / shares	12.88
Ending balance (in dollars per share) \| $ / shares	$ 10.04

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

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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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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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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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