Leases - Schedule of maturities of lease liabilities (Details) - USD ($) $ in Thousands	Mar. 28, 2020	Dec. 28, 2019
Operating Leases
2020	$ 10,997
2021	12,770
2022	8,956
2023	6,301
2024	4,034
Thereafter	6,940
Total lease payments	49,998
Less: Interest	(4,623)
Present value of lease liabilities	45,375
Finance Leases
2020	817
2021	964
2022	769
2023	483
2024	213
Thereafter	6
Total lease payments	3,252
Less: Interest	(452)
Present value of lease liabilities	$ 2,800	$ 2,707