Activity Under Equity Incentive Plans Related to Stock Options (Detail) - $ / shares	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Activity under the Company's equity incentive plans related to stock options
Exercised, Number of Options Outstanding	0	0
2008 Equity Incentive Plan
Activity under the Company's equity incentive plans related to stock options
Number of Options Outstanding, Beginning Balance	14,515,000
Granted, Number of Options Outstanding	0
Exercised, Number of Options Outstanding	0
Forfeited/canceled, Number of Options Outstanding	(2,218,000)
Number of Options Outstanding, Ending Balance	12,297,000	14,515,000
Weighted Average Exercise Price per Share
Weighted Average Exercise Price per Share, Beginning Balance	$ 5.2
Granted, Weighted Average Exercise Price per Share	0
Exercised, Weighted Average Exercise Price per Share	0
Forfeited/canceled, Weighted Average Exercise Price per Share	5.79
Weighted Average Exercise Price per Share, Ending Balance	$ 5.1	$ 5.2

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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.

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Gross number of share options (or share units) granted during the period.

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
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-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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

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

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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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

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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