Common Stock, Capital Shares Reserved for Future Issuance, Annual Increase, Percentage of Outstanding Common Stock

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Grant Date Fair Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercised in Period, Grant Date Fair Value

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Aggregate Fair Value

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- Definition

Tender Offer, Premium Price Per Share

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- Definition

Tender Offer, Shares Exchanged

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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

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-Name Accounting Standards Codification
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- Definition

Aggregate number of common shares reserved for future issuance.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount of paid and unpaid paid-in-kind dividends (PIK) declared for classes of stock, for example, but not limited to, common and preferred.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Subparagraph (SX 210.3-04)
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- Definition

Represents the compensation cost capitalized during the period arising from equity-based compensation arrangements (for example, shares of stock, units, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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.

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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unrecognized cost of unvested options awarded to employees as compensation.

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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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- 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.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Purchase price of common stock expressed as a percentage of its fair value.

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Stock-based Compensation - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended	12 Months Ended
	Jul. 27, 2017	Aug. 31, 2015	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)			21,188,297	73,655,190
Total grant date fair value, options vested			$ 10,571	$ 9,817	$ 4,917
Total grant date fair value, options exercised			3,002	911	1,373
Unrecognized stock-based compensation, options			18,187
Total fair value of options vested			274,192	71,592
Stock-based compensation expense		$ 772	11,101	8,413	5,562
Tender offer, premium price per share (in dollars per share)		$ 2.16
Tender offer, shares exchanged (in shares)		1,593,409
In-substance dividend issued in tender offer		$ 2,659			0
Stock-based compensation capitalized			$ 268	$ 100	$ 49
2017 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)			7,859,659
Percentage of common stock, outstanding			5.00%
Expected life			10 years
Award vesting period			4 years
Employee Stock \| 2017 Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)	1,600,000
Percentage of common stock, outstanding	1.00%
Purchase price of common stock, percentage of market price of common stock			85.00%
Employee Stock Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, period for recognition			2 years 3 months 18 days
Employee Stock Option \| 2004 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved (in shares)			0
Expected life			10 years
Award vesting period			4 years
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense, period for recognition			3 years 9 months
Unrecognized stock-based compensation, other than options			$ 21,856
Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tender offer, shares exchanged (in shares)		358,330
Non-Employee
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Tender offer, shares exchanged (in shares)		1,235,079