STOCK-BASED COMPENSATION - Narrative (Details) - USD ($)	12 Months Ended
	Jan. 01, 2017	Jan. 03, 2016	Dec. 28, 2014	Mar. 31, 2016	Mar. 21, 2016	Nov. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity award vesting period	4 years
Maximum contractual term	10 years
Stock-based compensation	$ 1,584,000	$ 2,028,000	$ 2,242,000
Weighted average estimated fair value (in dollars per share)	$ 0.46	$ 0.87	$ 1.99
Fair value of unvested stock options, net of forfeitures	$ 1,600,000
Closing stock price (in dollars per share)	$ 1.39			$ 1.00	$ 1.00	$ 2.90
The total intrinsic value of options exercised	$ 0	$ 83,000	$ 3,700,000
Total cash received from employees as a result of employee stock option exercises	0	117,000	4,500,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 486,000	$ 861,000	$ 1,100,000
Weighted average period	3 years 1 month 6 days
RSUs & PRSUs Outstanding
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ 953,000
PRSU
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation	$ (113,000)
Employee Stock Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period	4 years 6 months
Weighted average estimated fair value as defined by amended authoritative guidance (in dollars per share)	$ 0.62	$ 0.42	$ 0.96
Sales under ESPP (in shares)	732,000	458,000	278,000
Average price of sales under ESPP (in dollars per share)	$ 0.81	$ 1.26	$ 2.76
Shares available for issuance (in shares)	687,000
Compensation expenses related to ESPP	$ 258,000,000	$ 232,000	$ 255,000
Unrecognized stock-based compensation expense	$ 97,000