Income Taxes -Components of Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Jan. 03, 2016
schedule of income before income taxes domestic and foreign [Line Items]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ (25,667)	$ (11,002)	$ (18,787)