Long-Term Incentive Plans - Summary of Information Regarding Restricted Stock Awards (Detail) - 2017 Non-Employee Directors Compensation Plan [Member] - Restricted Stock Units (RSUs) [Member]	3 Months Ended
Mar. 31, 2020 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding, Number of Units, Beginning Balance \| shares	16,157
Granted, Number of Units \| shares	0
Forfeited, Number of Units \| shares	0
Vested, Number of Units \| shares	0
Outstanding, Number of Units, Ending Balance \| shares	16,157
Outstanding, Weighted-Average Grant Date Fair Value per unit, Beginning balance \| $ / shares	$ 5.12
Granted, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Forfeited, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Vested, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Outstanding, Weighted-Average Grant Date Fair Value per unit, Ending balance \| $ / shares	$ 5.12

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)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

+ References

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-Publisher FASB
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-Topic 718
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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).

+ References

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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.

+ References

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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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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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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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Long-Term Incentive Plans - Summary of Information Regarding Restricted Stock Awards (Detail) - 2017 Non-Employee Directors Compensation Plan [Member] - Restricted Stock Units (RSUs) [Member]	3 Months Ended
	Mar. 31, 2020 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Outstanding, Number of Units, Beginning Balance \| shares	16,157
Granted, Number of Units \| shares	0
Forfeited, Number of Units \| shares	0
Vested, Number of Units \| shares	0
Outstanding, Number of Units, Ending Balance \| shares	16,157
Outstanding, Weighted-Average Grant Date Fair Value per unit, Beginning balance \| $ / shares	$ 5.12
Granted, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Forfeited, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Vested, Weighted-Average Grant Date Fair Value per Unit \| $ / shares	0
Outstanding, Weighted-Average Grant Date Fair Value per unit, Ending balance \| $ / shares	$ 5.12