Earnings Per Share - Details of Basic and Diluted Earnings Per Share (EPS) from Continuing Operations (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ (705)	$ 5,045	$ 2,841	$ 9,087
Weighted average common shares outstanding used in basic EPS	43,792	43,617	43,754	43,601
Effect of dilutive SOSARs, PSAs and RSUs		565		809
Weighted average common shares outstanding and common share equivalents used in diluted EPS	43,792	44,182	43,754	44,410
Earnings (loss) per share from continuing operations
Basic	$ (0.02)	$ 0.12	$ 0.06	$ 0.21
Diluted	$ (0.02)	$ 0.11	$ 0.06	$ 0.21