Stock Option Award Activity (Detail) (Stock Option Plan, USD $) In Thousands, except Per Share data, unless otherwise specified	6 Months Ended
Jun. 30, 2014	Jun. 30, 2013
Stock Option Plan
Share based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options Outstanding, beginning	3,738	3,296
Number of Options, Granted	0	75
Number of Options, Exercised	(31)	(14)
Number of Options, Forfeited or expired	0	(15)
Number of Options Outstanding, ending	3,707	3,342
Number of Options exercisable	3,295	2,970
Weighted Average Exercise Price, beginning	$ 4.99	$ 5.50
Weighted Average Exercise Price, Granted	$ 0	$ 2.32
Weighted Average Exercise Price, Exercised	$ 1.30	$ 1.30
Weighted Average Exercise Price, Forfeited or expired	$ 0	$ 2.32
Weighted Average Exercise Price, ending	$ 5.02	$ 5.46
Weighted Average Exercise Price, Options exercisable	$ 5.42	$ 5.80

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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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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Net 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.

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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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No definition available.

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

+ References

No definition available.

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

+ References

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