Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
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Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

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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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

+ References

No definition available.

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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).

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The weighted average fair value at grant date for nonvested equity-based awards issued 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).

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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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Number of share instruments newly issued under a share-based compensation plan.

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- Definition

Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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-Publisher FASB
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Weighted average grant-date fair value of options vested.

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Stock-Based Compensation - Additional Information (Detail) - USD ($)	1 Months Ended		3 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Mar. 31, 2017	Mar. 31, 2016
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Grant date fair value of options vested, per share			$ 3.10	$ 3.06
Grant date fair value of options vested			$ 558,000	$ 444,000
Unrecognized compensation cost			$ 10,300,000
Weighted average period for recognition of compensation costs			3 years 3 months 18 days
Stock based compensation expenses			$ 769,000	556,000
Stock-based compensation expense capitalized			$ 0	$ 0
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs Granted			0
Grant date fair value of RSUs vested, per share		$ 3.58
Stock based compensation expenses			$ 0
Restricted Stock Units (RSUs) \| Board of Directors
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs Granted		112,578
Restricted Stock Units (RSUs) \| Executive Officers
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs Granted	18,017
RSUs Released			18,017
Restricted Stock Units (RSUs) \| Consultant
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
RSUs Granted	20,645