Stock Option Grants - Summary of Stock Option Activity (Detail) (USD $)	12 Months Ended
Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock Options Outstanding, Number of Shares, Beginning balance	0
Stock Options Granted, Number of Shares	83,400
Stock Options Exercised, Number of Shares	0
Stock Options Expired, Number of Shares	0
Stock Options Forfeited, Number of Shares	0
Stock Options Outstanding, Number of Shares, Ending balance	83,400
Stock Options Exercisable, Number of Shares	72,650
Stock Options Outstanding, Average Exercise Price, Beginning balance	$ 0
Stock Options Granted, Average Exercise Price	$ 8.09
Stock Options Exercised, Average Exercise Price	$ 0
Stock Options Expired, Average Exercise Price	$ 0
Stock Options Forfeited, Average Exercise Price	$ 0
Stock Options Outstanding, Average Exercise Price, Ending balance	$ 8.09
Stock Options Exercisable, Average Exercise Price	$ 8.10

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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

-Topic 718

-SubTopic 10

-Section 50

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-Subparagraph (c)(1)(iii)

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

+ References

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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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No definition available.

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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 of the plan that expired.

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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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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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