Emergence from Voluntary Reorganization under Chapter 11 - Additional Information (Detail) - USD ($)		6 Months Ended	8 Months Ended	12 Months Ended
	May 04, 2017	Jun. 30, 2019	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2019
Reorganizations [Line Items]
Common stock, par value				$ 0.0001	$ 0.01
Warrant issued during period				2,173,913	9,153,522
Plan Of Reorganization
Reorganizations [Line Items]
Percentage of new common shares issued to predecessor	2.00%
Aggregate cash amount to predecessor	$ 1,300,000
Plan Of Reorganization | Management Incentive Plan [Member]
Reorganizations [Line Items]
Aggregate shares of common stock available for grants	2,322,404
Noteholder Plan Support Agreement [Member]
Reorganizations [Line Items]
Percentage of new common shares issued	98.00%
Unsecured noteholders to receive pro rata share of cash distribution	$ 24,600,000
Credit Facility [Member] | Plan Of Reorganization
Reorganizations [Line Items]
Revolving credit facility	$ 1,000,000,000
Warrants [Member]
Reorganizations [Line Items]
Warrant life period	5 years
Percentage of common shares to be issued upon exercise of warrants	8.00%
Warrant issued during period	2,173,913
Warrant exercise price	$ 42.60
Common Stock [Member]
Reorganizations [Line Items]
Stock issued during period	25,000,000	0	0	0
Common stock, par value	$ 0.0001