Activity Under Equity Incentive Plans Related to Stock Options (Detail) - 2008 Equity Incentive Plan shares in Thousands	3 Months Ended
Mar. 31, 2023 $ / shares shares
Activity under the Company's equity incentive plans related to stock options
Number of Options Outstanding, Beginning Balance \| shares	15,756
Forfeited/canceled, Number of Options Outstanding \| shares	(858)
Number of Options Outstanding, Ending Balance \| shares	14,898
Weighted Average Exercise Price per Share
Weighted Average Exercise Price per Share, Beginning Balance \| $ / shares	$ 5.12
Forfeited/canceled, Weighted Average Exercise Price per Share \| $ / shares	3.69
Weighted Average Exercise Price per Share, Ending Balance \| $ / shares	$ 5.21

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

+ Details

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- Definition

Number of options outstanding, including both vested and non-vested options.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

+ References

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- Definition

Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

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