Aggregate number of common shares reserved for future issuance.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

+ References

No definition available.

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- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ 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 (j)
-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 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66902209&loc=d3e3255-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

+ Details

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

+ References

+ 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

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644

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- Definition

Share Based Compensation Arrangement by Share Based Payment Award, Contractual Life

+ References

No definition available.

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- Definition

Stock Repurchased During Period Per Share

+ References

No definition available.

+ Details

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Stock Option Plan - Additional information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended										12 Months Ended
	Dec. 31, 2016	Jun. 30, 2016	May 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	May 31, 2015	Dec. 31, 2014	Feb. 28, 2014	Jan. 31, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2012	Jun. 18, 2014	Dec. 31, 2013	May 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	26,364										26,364
Outstanding options issued	3,465,335			3,481,468				6,505,663			3,465,335	3,481,468	6,505,663			6,747,302
Proceeds from stock options exercised											$ 714	$ 4,568	$ 1,386
Total intrinsic value of options											1,500	$ 23,800	$ 2,600
Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period														3 years
Contractual terms														10 years
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual terms														10 years
Director \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period														3 years
Director \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period														1 year
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Repurchase of shares of restricted common stock	119,873	6,667	116,667	16,709	7,669			81,702	14,600	16,031
Repurchase of shares of restricted common stock, price per share	$ 5.35	$ 7.74	$ 6.86	$ 8.31	$ 11.57			$ 5.04	$ 4.40	$ 4.37
Restricted Stock \| Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years			3 years		3 years	3 years
Share-based payment award granted	625,750			403,083		50,000	1,000,000
Restricted Stock \| Non Employee Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year							1 year
Share-based payment award granted	86,020			133,305	4,186			66,828
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to non-vested restricted stock outstanding	$ 3,500										$ 3,500
Expected recognition period											1 year 5 months 16 days
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected recognition period											1 year 6 months 15 days
Share-based payment award granted											711,770	1,590,574	66,828
Unrecognized stock-based compensation expense related to non-vested restricted stock arrangements	$ 10,500										$ 10,500
the "2012 Plan"
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for future issuance	9,000,000										9,000,000				5,000,000		4,000,000
the "2012 Plan" \| Employees \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	2,652,835										2,652,835
the "2012 Plan" \| Director \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	802,500										802,500
the "2012 Plan" \| Consultants \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding options issued	10,000										10,000