Represents the number of active plans under which future awards may be granted.

No definition available.

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The period of time, from the grant date until the time at which the share-based [option] award expires.

+ References

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
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-SubTopic 10
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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

Unrecognized cost of unvested share-based compensation awards.

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-Name Accounting Standards Codification
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No definition available.

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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

The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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- Definition

The aggregate cash inflow comprised of the amount received from (a) employees to acquire the entity's shares under incentive awards, including stock option exercises and restricted stock arrangements, and (b) the excess tax benefit arising from such transactions.

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No definition available.

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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STOCK-BASED COMPENSATION (Details - Plan Information and P&L Impact) $ in Thousands	12 Months Ended
	Dec. 31, 2017 USD ($) plan shares	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Unrecognized compensation cost
Number of active plans \| plan	2
Term of plan	10 years
Proceeds and Excess Tax Benefit from Share-based Compensation	$ 12,900
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	23,361	$ 9,647	$ 8,508
Income tax benefit related to non-cash compensation	9,500	3,700	3,000
Cost of revenue
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	175	129	95
Selling and marketing expense
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	3,973	2,722	1,597
General and administrative expense
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	16,874	4,699	5,120
Product development
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	2,339	2,097	1,558
Restructuring and severance
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	0	$ 0	$ 138
Employee Stock Option 2 [Member]
Unrecognized compensation cost
Unrecognized compensation cost	$ 2,300
Weighted-average period for recognition of unrecognized compensation cost	1 year 7 months 20 days
Employee Stock Option [Member]
Unrecognized compensation cost
Unrecognized compensation cost	$ 12,100
Weighted-average period for recognition of unrecognized compensation cost	6 months 28 days
Performance Shares [Member]
Non-cash compensation expense related to equity awards
Non-cash stock-based compensation expense before income taxes	$ 3,100
RSUs
Unrecognized compensation cost
Unrecognized compensation cost	$ 13,900
Weighted-average period for recognition of unrecognized compensation cost	1 year 9 months 20 days
Restricted Stock
Unrecognized compensation cost
Unrecognized compensation cost	$ 13,500
Weighted-average period for recognition of unrecognized compensation cost	1 year 8 months 8 days
Equity Award Plan [Member]
Unrecognized compensation cost
Number of shares authorized \| shares	5,350,000.00
Inducement Plan [Member]
Unrecognized compensation cost
Number of shares authorized \| shares	500,000.0