INCOME TAXES - Schedule of U.S. and Foreign Components of Consolidated Income (Loss) before Income Taxes and Provision for (Benefit from) Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
Income (loss) before income taxes:
U.S.	$ (14,253)	$ (19,340)	$ (17,897)
Foreign	209	257	195
Income (loss) before income taxes	(14,044)	(19,083)	(17,702)
Current:
Federal	0	0	37
State	2	(3)	2
Foreign	85	75	99
Subtotal	87	72	138
Deferred:
Federal	0	0	0
State	0	0	0
Foreign	0	(7)	8
Subtotal	0	(7)	8
Provision for income taxes	$ 87	$ 65	$ 146