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

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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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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Common Stock and Stock-Based Awards - Stock Options - Additional Information (Detail) - USD ($)	3 Months Ended			6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of stock options	$ 2.41	$ 2.38		$ 2.17	$ 4.34
Performance-based stock options to granted				4,324,865
Stock based compensation expense for stock options	$ 1,914,000	$ 2,097,000		$ 3,873,000	$ 4,162,000
Performance Shares [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of stock options			$ 4.58
Performance-based stock options to granted			1,100,000
Stock options exercisable	0			0
Stock based compensation expense for stock options				$ 0