Cash, Cash Equivalents, Restricted Cash And Investments - Summary of Debt Securities, Available-for-Sale, Unrealized Loss Position, Fair Value (Detail) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months, Fair Value	$ 233,884	$ 136,974
Less than 12 Months, Gross Unrealized Losses	(377)	(264)
12 Months or Longer, Fair value	132,124	180,916
12 Months or Longer, Gross Unrealized Losses	(1,377)	(2,042)
Total, Fair value	366,008	317,890
Total, Gross Unrealized Loses	(1,754)	(2,306)
Commercial Paper [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months, Fair Value	3,989	16,360
Less than 12 Months, Gross Unrealized Losses	(3)	(14)
12 Months or Longer, Fair value	0	0
12 Months or Longer, Gross Unrealized Losses	0	0
Total, Fair value	3,989	16,360
Total, Gross Unrealized Loses	(3)	(14)
Corporate Notes and Bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months, Fair Value	9,128	11,074
Less than 12 Months, Gross Unrealized Losses	(46)	(58)
12 Months or Longer, Fair value	104,889	151,174
12 Months or Longer, Gross Unrealized Losses	(1,204)	(1,796)
Total, Fair value	114,017	162,248
Total, Gross Unrealized Loses	(1,250)	(1,854)
Municipal Bonds [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months, Fair Value		0
Less than 12 Months, Gross Unrealized Losses		0
12 Months or Longer, Fair value		4,947
12 Months or Longer, Gross Unrealized Losses		(43)
Total, Fair value		4,947
Total, Gross Unrealized Loses		(43)
US government and agency [Member]
Debt Securities, Available-for-Sale [Line Items]
Less than 12 Months, Fair Value	220,767	109,540
Less than 12 Months, Gross Unrealized Losses	(328)	(192)
12 Months or Longer, Fair value	27,235	24,795
12 Months or Longer, Gross Unrealized Losses	(173)	(203)
Total, Fair value	248,002	134,335
Total, Gross Unrealized Loses	$ (501)	$ (395)