Leases - lease assets and our lease liabilities (Detail) - USD ($) $ in Thousands	Mar. 30, 2019	Dec. 30, 2018	Dec. 29, 2018
Assets:
Operating lease right-of-use assets	$ 11,076	$ 11,635
Liabilities:
Current operating lease liabilities	2,569	2,581
Noncurrent operating lease liabilities	10,491	11,120
Operating Lease, Liability	$ 13,060	$ 13,701