Stockholders' Deficit Common Stock - Stock Options - Additional Information (Detail) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant-date fair value of stock options	$ 2.12	$ 5.67	$ 4.24	$ 6.83
Performance-based stock options to granted			2,346,350
Stock based compensation expense for stock options	$ 2,037,000	$ 4,317,000	$ 6,199,000	$ 12,887,000
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

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

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