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.

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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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.

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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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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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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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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.

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

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No definition available.

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

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

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Equity (Details) - USD ($) $ / shares in Units, $ in Thousands			3 Months Ended	12 Months Ended
	May 17, 2017	May 04, 2017	Mar. 31, 2017	Dec. 31, 2016
Options
Share-based compensation
Options units outstanding (in shares)			12,938	12,938
Option units available for grant (in shares)			47,062
Options forfeited (in shares)		366
Vesting period			4 years
Stock-based compensation expense			$ 32	$ 36
Unrecognized compensation costs			$ 291	$ 323
Options \| Class A common stock
Share-based compensation
Options granted (in shares)	591,261
Options granted (in dollars per shares)	$ 2.87
Options \| Class A common stock \| First vesting period
Share-based compensation
Vesting (as a percent)	25.00%
Options \| Class A common stock \| Second vesting period
Share-based compensation
Vesting (as a percent)	25.00%
Restricted stock
Share-based compensation
Restricted stock, granted	648,676
Restricted stock \| First vesting period
Share-based compensation
Vesting period	1 year
Restricted stock, granted	203,222
Restricted stock \| Second vesting period
Share-based compensation
Vesting period	3 years
Restricted stock, granted	445,454
Subsequent Events \| Class A common stock
Share-based compensation
Reserved for issuance (in shares)	5,118,080