Number of shares issued pursuant to the terms of a deferred compensation arrangement.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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Net 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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Stock-Based Compensation - Additional Information (Detail) - USD ($)		3 Months Ended
	Jan. 06, 2019	Mar. 31, 2020	Mar. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted		896,000	1,496,333
Weighted-average grant date fair value		$ 2.64	$ 1.62
Number of shares issued for accrued annual performance bonus	446,428
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding		$ 10,100,000
Expected recognition period		1 year 9 months 10 days
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding		$ 4,500,000
Expected recognition period		1 year 7 months 2 days