Employee Stock Purchase Plan Offering Period

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Additional Term

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Ratable Vesting Percentage

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Award Ratable Vesting Period

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Common Stock Equivalent Ratio

+ References

No definition available.

+ Details

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants Date Total Fair Value

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Vested on the First Anniversary, Vesting Percentage

+ References

No definition available.

+ Details

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- Definition

Amount of discretionary contributions made by an employer to a defined contribution plan.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

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

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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.

+ 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)(2)

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

+ Details

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- Details

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- Definition

The highest percentage of annual salary that an employee is permitted to utilize with respect to the plan.

+ References

+ Details

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Period Type:	instant

- Definition

The highest quantity of shares an employee can purchase under the plan per period.

+ References

+ Details

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Period Type:	duration

- 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

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

+ Details

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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

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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- Definition

The weighted average of per share prices paid for shares purchased on the open market for issuance to employees under the 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

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5047-113901

+ Details

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Balance Type:	na
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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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EMPLOYEE STOCK PLANS - Narrative (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2013	May 31, 2012	May 31, 2014
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percent of options vesting on first anniversary of vesting commencement date	25.00%
Options granted in period (in shares)	700,000	1,600,000	3,100,000
Options, grant date fair value	$ 0.9	$ 1.4	$ 2.9
Defined contribution plan, employer discretionary contribution amount	$ 0.2	$ 0.1	$ 0.2
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate	2.78%
Time-based restricted stock units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting rate				25.00%
Grant ratio	1.75
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares of additional common stock approved (in shares)					2,500,000
Number of shares reserved for issuance (in shares)					17,000,000
Number of shares available for future grant (in shares)	3,300,000
2012 Equity Incentive Plan \| Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price, as a percent of fair market value of common stock on grant date	100.00%
Percent of options vesting on first anniversary of vesting commencement date	25.00%
Vesting period	36 months
Employee requisite service period				1 year
2012 Equity Incentive Plan \| Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award terms	7 years
1994 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
ESPP extended term						10 years
ESPP offering period	6 months
1994 Plan \| Employee stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares reserved for issuance (in shares)	6,200,000
Number of shares available for future grant (in shares)	2,500,000
Exercise price, as a percent of fair market value of common stock on grant date	90.00%
Maximum employee subscription rate	15.00%
Maximum number of shares per employee (in shares)	4,000	2,000
Shares issued in period (in shares)	100,000	100,000	100,000
Average price of shares purchased, per share (in usd per share)	$ 2.17	$ 2.09	$ 1.23	2.09