Activity Under Equity Incentive Plans Related to Stock Options (Detail)	12 Months Ended
Dec. 31, 2023 $ / shares shares
Activity under the Company's equity incentive plans related to stock options
Exercised, Number of Options Outstanding	0
2008 Equity Incentive Plan
Activity under the Company's equity incentive plans related to stock options
Number of Options Outstanding, Beginning Balance	15,756,000
Forfeited/canceled, Number of Options Outstanding	(1,241,000)
Number of Options Outstanding, Ending Balance	14,515,000
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	4.20
Weighted Average Exercise Price per Share, Ending Balance \| $ / shares	$ 5.20

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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

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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
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Publisher FASB
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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.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Section 50
-Paragraph 2
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