Equity - Summary of Stock Option Activity (Detail)	6 Months Ended
Jun. 30, 2017 $ / shares shares
Equity [Abstract]
Stock options, beginning balance \| shares	5,136,110
Stock options, granted \| shares	1,993,998
Stock options, exercised \| shares	329,819
Stock options, canceled or expired \| shares	53,265
Stock options, ending balance \| shares	6,747,024
Stock options, exercisable, ending balance \| shares	2,195,147
Weighted average exercise price, beginning balance \| $ / shares	$ 5.76
Weighted average exercise price, granted \| $ / shares	7.54
Weighted average exercise price, exercised \| $ / shares	3.14
Weighted average exercise price, canceled or expired \| $ / shares	2.34
Weighted average exercise price, ending balance \| $ / shares	6.44
Weighted average exercise price, exercisable, ending balance \| $ / shares	$ 5.33

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- Definition

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

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)(iii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

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)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

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.

+ References

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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