Components of Calculation of Basic and Diluted Earnings Per Share (Detail) - USD ($) shares in Thousands, $ in Thousands		4 Months Ended	12 Months Ended
		Dec. 31, 2016	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Net loss attributable to common shareholders		$ 32,662	$ 70,589	$ 224,785
Weighted-average shares – basic		14,996	15,110	15,059	14,996
Effect of dilutive securities	[1]	67	16	233
Weighted-average shares – diluted		15,063	15,126	15,292	15,063

[1] Represents a combination of unvested RSUs and PRSUs that are dilutive with the exception of December 31, 2019 at which time all of our unvested PRSUs were determined to be at a zero percent vesting level due to the relative performance of our common stock.