Common and Common Equivalent Shares - Schedule of Calculation of Shares Used in Basic and Diluted Net Income Per Share (Detail) - shares shares in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Weighted average number of common shares outstanding		83,862	82,441	83,260	83,846
Weighted average number of dilutive common share equivalents			442		456
Weighted average number of common and common equivalent shares outstanding	[1]	83,862	82,883	83,260	84,302
Antidilutive securities not included in the diluted net income per common share calculation		829	962	1,004	796

[1] Due to a loss from continuing operations for the three months and nine months ended September 30, 2020, no incremental shares are included because the effect would be antidilutive.