Stock Incentive Plan - Summary of Stock Option Activity (Detail) (USD $)	0 Months Ended	12 Months Ended
Jun. 21, 2013	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award, Options Outstanding, Weighted Average Exercise Price, and Additional Disclosures [Abstract]
Stock Options Outstanding, Beginning Balance		609,842	67,232
Stock Options, Granted	300,147	264,190	542,610
Stock Options Outstanding, Ending Balance		874,032	609,842
Weighted Average Exercise Price, Beginning Balance		$ 1.48	$ 3.24
Weighted Average Exercise Price, Granted	$ 3.24	$ 6.84	$ 1.26
Weighted Average Exercise Price, Ending Balance		$ 3.10	$ 1.48

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

+ References

No definition available.

+ Details

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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/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)-(ii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(i)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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