Earnings Per Share - Reconciliation of Basic and Diluted Shares Amounts (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Numerator
Net Income (Loss)	$ 20,064	$ 49,861	$ 48,893	$ 96,825
Effect of dilutive securities
Charges associated with convertible debt instruments, net of tax	0	0	0	387
Numerator for diluted earnings per share - net income available to common stockholders after the effect of dilutive securities	$ 20,064	$ 49,861	$ 48,893	$ 97,212
Denominator
Weighted average shares used in computing net income per share - basic	55,705	55,444	55,648	55,399
Effect of dilutive shares
Options and stock units	451	598	487	661
Convertible Senior Notes	701	676	797	1,779
Dilutive effect of unvested performance stock units	1	3	1	3
Dilutive potential common shares	1,153	1,277	1,284	2,443
Denominator for diluted earnings per share - adjusted weighted average shares used in computing net income per share - diluted	56,858	56,721	56,932	57,842
Earnings per share:
Basic	$ 0.36	$ 0.9	$ 0.88	$ 1.75
Diluted (Note 11)	$ 0.35	$ 0.88	$ 0.86	$ 1.68