(10) Concentrations of Credit Rick, Significant Customers and Geographic Information - Revenue derived from following countries (Details)	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018
Percent of Total Revenues Country
United States of America	25.00%	33.00%
Germany	44.00%	53.00%
Other	31.00%	14.00%