Summary of Status of Company's Stock Option Plan (Detail) (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Shares
Granted	1,055,500	173,354
Stock Option Plan
Shares
Outstanding at beginning of period	2,517,911	3,348,935
Cancelled		(58,617)
Exercised	(292,537)	(945,761)
Granted	1,055,500	173,354
Outstanding at end of period	3,280,874	2,517,911
Weighted Average Exercise Price
Outstanding at beginning of period	1.33	1.23
Cancelled		1.87
Exercised	1.03	1.20
Granted	3.28	2.59
Outstanding at end of period	1.98	1.33

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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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iv)(3)

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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