Stockholders' Equity - Components of Stockholders' Equity (Detail) - USD ($)		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Beginning Balance		$ 240,265,000	$ 221,656,000
Issuance of common stock under stock plans, including tax effects		$ (176,000)	$ 761,000
Repurchases of common stock, Shares		200,000	0
Repurchases of common stock		$ (4,097,000)
Stock-based compensation expense		$ 3,574,000	$ 3,165,000
Accounting Standards Update [Extensible List]		us-gaap:AccountingStandardsUpdate201613Member
Net loss		$ (6,673,000)	(4,075,000)
Net change in marketable investments, net of tax		6,000	33,000
Foreign currency translation		(1,968,000)	1,206,000
Ending Balance		230,931,000	222,746,000
Common Stock [Member]
Beginning Balance		$ 247,000	$ 244,000
Beginning Balance, Shares		24,684,000	24,367,000
Issuance of common stock under stock plans, including tax effects		$ 2,000	$ 1,000
Issuance of common stock under,stock plans including tax effects, Shares		197,000	128,000
Ending Balance		$ 249,000	$ 245,000
Ending Balance, Shares		24,881,000	24,495,000
Additional Paid-in Capital [Member]
Beginning Balance		$ 278,057,000	$ 261,766,000
Issuance of common stock under stock plans, including tax effects		(178,000)	760,000
Stock-based compensation expense		3,574,000	3,165,000
Ending Balance		281,453,000	265,691,000
Retained Earnings [Member]
Beginning Balance		177,681,000	174,631,000
Net loss		(6,673,000)	(4,075,000)
Ending Balance		171,008,000	170,556,000
Treasury Stock [Member]
Beginning Balance		$ (211,149,000)	$ (207,067,000)
Beginning Balance, Shares		5,437,000	5,305,000
Repurchases of common stock, Shares		202,000
Repurchases of common stock		$ (4,097,000)
Ending Balance		$ (215,246,000)	$ (207,067,000)
Ending Balance, Shares		5,639,000	5,305,000
Accumulated Other Comprehensive Loss [Member]
Beginning Balance		$ (4,571,000)	$ (7,918,000)
Net change in marketable investments, net of tax		6,000	33,000
Foreign currency translation	[1]	(1,968,000)	1,206,000
Ending Balance		$ (6,533,000)	$ (6,679,000)

[1] The Company does not record tax provisions or benefits for the net changes in foreign currency translation adjustments as it intends to permanently reinvest undistributed earnings of its foreign subsidiaries.