Earnings per Share/Unit - Calculation of Earnings (Loss) per Share/Unit (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended								4 Months Ended	8 Months Ended	12 Months Ended
		Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	May 04, 2017	Dec. 31, 2017	Dec. 31, 2019	Dec. 31, 2018
Earnings Per Share/Unit [Line Items]
Net income (loss) attributable to Successor/Predecessor		$ (27,518)	$ 5,157	$ 18,641	$ (31,477)	$ 79,247	$ (2,598)	$ (25,279)	$ 3,239		$ 1,286	$ (35,197)	$ 54,609
Less: Net income (loss) allocated to participating restricted stockholders											35	0	2,426
Basic and diluted earnings available to common stockholders/limited partners											$ 1,251	$ (35,197)	$ 52,183
Common shares/units:
Common shares/units outstanding — basic											25,000	29,301	24,959
Common shares/units outstanding — diluted											25,000	29,301	24,959
Net earnings per share/unit:
Basic											$ 0.05	$ (1.20)	$ 2.09
Diluted											$ 0.05	$ (1.20)	$ 2.09
Predecessor [Member]
Earnings Per Share/Unit [Line Items]
Net income (loss) attributable to Successor/Predecessor										$ (90,955)
Less: Net income (loss) allocated to participating restricted stockholders										0
Basic and diluted earnings available to common stockholders/limited partners										$ (90,955)
Common shares/units:
Common shares/units outstanding — basic										83,807
Common shares/units outstanding — diluted										83,807
Net earnings per share/unit:
Basic										$ (1.09)
Diluted										$ (1.09)
Stock Options [Member]
Net earnings per share/unit:
Antidilutive stock options or warrants	[1]										517
Warrants [Member]
Net earnings per share/unit:
Antidilutive stock options or warrants	[2]										2,174	9,154	2,174

[1] Amount represents options to purchase common stock that are excluded from the diluted net earnings per share calculations because of their antidilutive effect.

[2] Amount represents warrants to purchase common stock that are excluded from the diluted net earnings per share calculations because of their antidilutive effect.