Earnings per Share - Summary of Computation for Basic and Diluted Net Earnings (Loss) per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Numerator
Numerator for basic and diluted earnings (loss) per share		$ 4,996	$ 1,043	$ 4,815	$ (6,722)
Weighted average common shares outstanding:
Basic weighted average common shares outstanding		166,375	163,119	165,838	162,109
Dilutive effects of stock options and share-based awards issuable under equity compensation plans		3,280	5,384	3,921
Diluted weighted average common shares outstanding		169,655	168,503	169,759	162,109
Computation of:
Basic net earnings (loss) per share		$ 0.03	$ 0.01	$ 0.03	$ (0.04)
Diluted net earnings (loss) per share		$ 0.03	$ 0.01	$ 0.03	$ (0.04)
Anti-dilutive common stock equivalents	[1]	8,596	5,000	6,719	19,080

[1] These common stock equivalents were outstanding for the period but were not included in the computation of diluted EPS for those periods as their inclusion would have had an anti-dilutive effect.