Activity Under Equity Incentive Plans Related to RSUs (Detail) - 2008 Equity Incentive Plan - Restricted Stock Units shares in Thousands	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Activity under the Company's equity incentive plans related to restricted stock units
Number of Restricted Stock Units Unvested, Beginning Balance | shares	6,690
Granted, Number of Restricted Stock Units Unvested | shares	5,330	[1]
Vested, Number of Restricted Stock Units Unvested | shares	(2,880)	[1]
Forfeited, Number of Restricted Stock Units Unvested | shares	(643)	[1]
Number of Restricted Stock Units Unvested, Ending Balance | shares	8,497
Weighted Average Exercise Price per Share
Weighted Average Exercise Price per Share, Beginning Balance | $ / shares	$ 5.90
Granted, Weighted Average Exercise Price per Share | $ / shares	5.55	[1]
Vested, Weighted Average Exercise Price per Share | $ / shares	5.66	[1]
Forfeited, Weighted Average Exercise Price per Share | $ / shares	6.00	[1]
Weighted Average Exercise Price per Share, Ending Balance | $ / shares	$ 5.76

[1] Includes shares issuable under performance-based restricted stock unit awards.