EMPLOYEE STOCK PLANS - Narrative (Details) - $ / shares		6 Months Ended
May. 28, 2015	Jun. 28, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Average purchase price (in usd per share)		$ 2.05
Time-based Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage vest on each anniversary of the vesting commencement date or date of grant		25.00%
Common stock equivalent shares		1.75
2012 Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)		3,900,000
Additional number of shares reserved for issuance (in shares)	2,500,000.0
Number of shares reserved for issuance (in shares)	19,475,000
Common stock equivalent shares		1.75
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%
Vesting percentage, first anniversary		25.00%
Award ratable vesting percentage per month		2.08%
Requisite service period to vest over 4 years		1 year
Award ratable vesting period		4 years
2012 Equity Incentive Plan \| Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award terms		7 years
1994 Employee Stock Purchase Plan \| Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares available for grant (in shares)		2,500,000
Number of shares reserved for issuance (in shares)		6,200,000
Exercise price, as a percent of fair market value of common stock on grant date		90.00%
Maximum employee subscription rate		15.00%
ESPP offering period		6 months
Maximum number of shares per employee (in shares)		4,000
Shares issued in period (in shares)		40,000
Average purchase price (in usd per share)		$ 3.51

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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

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- 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

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

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

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- Definition

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

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- Definition

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

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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

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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.

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- Definition

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

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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

Percentage of vesting of share-based compensation awards.

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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

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- Definition

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

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