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

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(3)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (c)(1)(iii)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-Section 50

-Paragraph 2

-Subparagraph (d)(1)

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- Definition

Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

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

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No definition available.

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Represents the annual increase in maximum number of shares (or other type of equity) approved (usually by shareholders and board of directors), for awards under the equity-based compensation plan.

+ References

No definition available.

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Represents the annual percentage increase in maximum number of shares (or other type of equity) approved (usually by shareholders and board of directors), for awards under the equity-based compensation plan.

+ References

No definition available.

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- Definition

The initial period of time from the date the plan becomes effective until it expires.

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No definition available.

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- Definition

Represents the number of six month purchase periods included in the initial term of the plan.

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No definition available.

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- Definition

The percentage of annual compensation that employees may elect to have withheld to purchase stock at a discount.

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No definition available.

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- Definition

Represents the purchase period during which the employee withholding amounts may be used to purchase shares.

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No definition available.

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- Definition

Represents the purchase price expressed as a percentage of the fair market value of common stock at the initial offering date.

+ References

No definition available.

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Stock-Based Compensation (Details) (USD $)	12 Months Ended			0 Months Ended	13 Months Ended
Stock-Based Compensation (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 01, 2014	Dec. 31, 2014 item	Dec. 02, 2013
Stock options
Stock-based compensation
Total number of shares of common stock available for issuance	2,583,186	2,403,368	753,692		2,583,186
Information with respect to stock options outstanding
Exercisable options (in shares)	1,393,729	1,203,885	1,094,573		1,393,729
Weighted-average exercise price per share of exercisable options (in dollars per share)	$ 1.01	$ 0.59	$ 0.59		1.01
Weighted average grant date fair value per share of options granted during the year (in dollars per share)	$ 7.39	$ 3.78	$ 0.34
Weighted-average remaining contractual life	6 years 5 months 5 days	5 years 8 months 19 days	7 years 9 months 15 days
The 2010 Plan
Stock-based compensation
Total number of shares of common stock available for issuance	0				0
The 2013 Plan
Stock-based compensation
Total number of shares of common stock available for issuance	5,409,980				5,409,980
Annual percentage increase in shares of common stock available for issuance	4.00%
Increase in shares of common stock available for issuance (in shares)				1,254,179
Prior Plans
Stock-based compensation
Total number of shares of common stock available for issuance						2
Employee Stock Purchase Plan
Stock-based compensation
Total number of shares of common stock available for issuance	581,286				581,286
Initial term of plan	2 years
Number of six month purchase periods	4				4
Purchase period	6 months
Increase in shares of common stock available for issuance (in shares)				313,545
Awards issued under the plan (in shares)					63,864
Employee Stock Purchase Plan \| Minimum
Stock-based compensation
Percentage of compensation that employees may withhold to purchase stock at a discount	1.00%				1.00%
Employee Stock Purchase Plan \| Maximum
Stock-based compensation
Percentage of compensation that employees may withhold to purchase stock at a discount	15.00%				15.00%
Purchase price as percentage of stock price at the initial offering date	85.00%
Purchase price as percentage of stock price at the purchase date	85.00%
Annual percentage increase in shares of common stock available for issuance	1.00%
Annual increase in shares of common stock available for issuance (in shares)	621,814