Increase decrease in treasury shares for income tax purposes.

No definition available.

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- Definition

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.

+ References

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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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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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.

+ References

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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.

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

+ References

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- Definition

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.

+ References

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- Definition

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

+ References

No definition available.

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- Definition

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

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- Definition

Number of share options (or share units) exercised during the current period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended
	Apr. 30, 2017	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Maximum shares of common stock authorized for issuance under stock option plan (in shares)		5,500,000.0
Increase in treasury shares (in shares)		8,000
Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options to purchase shares outstanding under share based compensation (in shares)		853,366		861,366
Number of stock options granted (in shares)		0	0
Options exercised in period (in shares)		0	0
Unrecognized compensation cost		$ 241,000
Expected weighted-average period for recognized compensation cost		1 year 9 months
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost		$ 6,100,000
Expected weighted-average period for recognized compensation cost		2 years 5 months 1 day
General and Administrative Expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ 34,000	$ 0
General and Administrative Expenses \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		1,200,000	850,000
General and Administrative Expenses \| RSUs \| Habits at Work
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense		$ (57,000)	$ 305,000
Subsequent Event
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized and reserved for issuance (in shares)	4,000,000.0
Maximum shares of common stock authorized for issuance under stock option plan (in shares)	9,500,000.0
2014 Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares remaining to be granted under stock option plan (in shares)		2,500,000
Options to purchase shares outstanding under share based compensation (in shares)		3,200,000