Gross Amounts and Dates of Expiration of Tax Credits and Carryovers (Detail) - USD ($) $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Line Items]
Federal losses carryovers	$ 559,551
California loss carryovers	108,685
Other state loss carryovers	45,090
Research credits	29,739	$ 28,567
Federal foreign tax credits	610
Federal
Income Tax Disclosure [Line Items]
Research credits	17,074
California
Income Tax Disclosure [Line Items]
Research credits	16,011
Expires 2025-2027
Income Tax Disclosure [Line Items]
Federal losses carryovers	58,345
Other state loss carryovers	128
Federal foreign tax credits	610
Expires 2025-2027 | Federal
Income Tax Disclosure [Line Items]
Research credits	1,279
Expires 2028-2034
Income Tax Disclosure [Line Items]
Federal losses carryovers	193,684
California loss carryovers	67,796
Other state loss carryovers	2,762
Expires 2028-2034 | Federal
Income Tax Disclosure [Line Items]
Research credits	1,927
Expires 2035-2044
Income Tax Disclosure [Line Items]
Federal losses carryovers	116,604
California loss carryovers	40,889
Other state loss carryovers	30,630
Expires 2035-2044 | Federal
Income Tax Disclosure [Line Items]
Research credits	13,868
No Expiration
Income Tax Disclosure [Line Items]
Federal losses carryovers	190,918
Other state loss carryovers	11,570
No Expiration | California
Income Tax Disclosure [Line Items]
Research credits	$ 16,011