Unrecognized cost of unvested share-based compensation awards.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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

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- Definition

Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
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-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
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-Section 50
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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.

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No definition available.

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- Definition

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

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ 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 (d)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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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=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Topic 718
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-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
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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.

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- Definition

Percentage of vesting of share-based compensation awards.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Options Grants Grant Date Fair Value

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted		593,500	21,300	859,000	157,300
Weighted-average grant date fair value		$ 4.29	$ 3.71	$ 4.34	$ 5.36
Stock options granted exercise price				$ 6.28
Stock options outstanding	3,622,335	3,622,335		3,622,335		3,465,335
Stock options remaining contractual life				6 years 2 months 19 days
Outside 2012 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock options, granted	500,000
Stock options granted exercise price	$ 6.16
Share Based compensation arrangement by share based payment award options grants grant date fair value	$ 2,200	$ 2,200		$ 2,200
Stock options outstanding	500,000	500,000		500,000
Stock options remaining contractual life	10 years
Outside 2012 Plan \| The next three grant date anniversaries vesting percentage
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation, award vesting rights, percentage	33.33%
Accounting Standards Update 2016-09 [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cumulative effect adjustment	$ (122)	$ (122)		$ (122)
Unvested Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation costs related to unvested restricted stock outstanding	5,000	5,000		$ 5,000
Expected recognition period				1 year 8 months 16 days
Unvested Restricted Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected recognition period				1 year 3 months 29 days
Unrecognized stock-based compensation expense related to unvested restricted stock	$ 6,000	$ 6,000		$ 6,000