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
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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.

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

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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.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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- Definition

The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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No definition available.

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Stock-Based Compensation - Restricted Stock Awards (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Restricted Stock Units (RSUs)
Number of Shares
Granted (shares)			194,000
Weighted-Average Grant Date Fair Value per Share
Vesting period			4 years
Restricted Stock Awards
Number of Shares
Unvested, beginning balance (shares)			46,000
Granted (shares)			9,000
Vested (shares)			(38,000)
Forfeited (shares)			0
Unvested, ending balance (shares)	17,000		17,000
Weighted-Average Grant Date Fair Value per Share
Unvested, beginning balance (usd per share)			$ 8.55
Granted (usd per share)			33.30
Vested (usd per share)			9.33
Forfeited (usd per share)			0.00
Unvested, ending balance (usd per share)	$ 19.79		$ 19.79
Stock-based compensation expense	$ 84	$ 113	$ 274	$ 342
Remaining stock-based compensation expense for unvested shares, not yet recognized	$ 268		$ 268
Stock-based compensation expense, weighted average recognition period			9 months
Employee \| Restricted Stock Awards
Weighted-Average Grant Date Fair Value per Share
Vesting period			4 years
Non-Employee Director \| Restricted Stock Awards
Weighted-Average Grant Date Fair Value per Share
Vesting period			1 year