Share-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Recognized share-based compensation awards	$ 0.5	$ 1.0	$ 1.2	$ 2.8
Share-based compensation arrangement options, grants	1,200,000	0	1,200,000	0
Estimated weighted average fair value of stock option granted	$ 1.98		$ 1.98
Expected volatility rate	52.50%		52.50%
Expected term period	5 years		5 years
Risk free interest rate	0.30%		0.30%
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercised, Number of Shares			0	1,000
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of restricted stock awards granted	144,000	0	648,000	464,000
Weighted-average fair value of restricted stock unit granted			$ 6.35	$ 7.49

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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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 risk-free interest rate assumption that is used in valuing an option on its own shares.

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Rate of weighted-average expected volatility for award 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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Gross number of share options (or share units) granted during the period.

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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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Expected term of 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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Number of share options (or share units) exercised during the current period.

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