Operating Segment and Geographic Information - Net sales by geographic region/country (Details) - USD ($) $ in Thousands	3 Months Ended						4 Months Ended		12 Months Ended
	Dec. 28, 2019	Oct. 05, 2019	Mar. 23, 2019	Dec. 29, 2018	Oct. 06, 2018	Mar. 24, 2018	Jul. 13, 2019	Jul. 14, 2018	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Segment Reporting Information [Line Items]
Net Sales	$ 47,044	$ 45,756	$ 32,102	$ 50,992	$ 43,955	$ 32,149	$ 55,639	$ 48,684	$ 180,541	$ 175,780	$ 177,333
North America [Member]
Segment Reporting Information [Line Items]
Net Sales									178,069	172,656	175,065
Europe [Member]
Segment Reporting Information [Line Items]
Net Sales									1,001	965	974
Other [Member]
Segment Reporting Information [Line Items]
Net Sales									$ 1,471	$ 2,159	$ 1,294