The Company and Significant Accounting Policies - Summary of Components of AOCI (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Beginning	$ 288,172	$ 332,732
Other comprehensive income (loss)	(500)
Income tax (expense) benefit	100
Total other comprehensive income (loss)	(389)	793
Balance, Ending	248,237	323,730
Foreign Currency Translation
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Beginning	(500)
Other comprehensive income (loss)	(200)
Total other comprehensive income (loss)	(200)
Balance, Ending	(700)
Marketable Securities
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Beginning	400
Other comprehensive income (loss)	(300)
Income tax (expense) benefit	100
Total other comprehensive income (loss)	(200)
Balance, Ending	200
Accumulated Other Comprehensive Income (Loss)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance, Beginning	(131)	(1,412)
Balance, Ending	$ (520)	$ (619)