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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Unrecognized cost of unvested share-based compensation awards.

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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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- Definition

Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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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.

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The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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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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- Definition

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

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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).

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

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- Definition

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

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

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Stock-Based Compensation - Narrative (Details) - USD ($) $ in Thousands		12 Months Ended
	Jun. 21, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Jul. 10, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from exercise of stock options, shares		141,840	67,000
Proceeds from exercise of stock options		$ 229	$ 111	$ 54
Expected dividend yield		0.00%
Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under plan (in shares)		438,712	185,260	408,710
Stock-based compensation expense		$ 600	$ 700	$ 500
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Proceeds from exercise of stock options		200	100
Compensation cost not yet recognized		$ 1,700
Compensation cost not yet recognized, period for recognition		5 years 10 months 18 days
Selling, General and Administrative Expense
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense		$ 800	$ 900	$ 800
Global Share Option Plan and Israeli Sub-Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock underlying options outstanding (in shares)		1,489,532
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized under plan (in shares)					2,196,836
Shares available for issuance under plan (in shares)		749,443
2014 Plan \| Restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under plan (in shares)		576,212	200,000
2014 Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options granted (in shares)		898,334	295,000
Finjan Holdings, Inc. 2014 Incentive Compensation Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)	1,000,000