Stockholders' Equity Summary of stock option activity (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Mar. 31, 2016	Dec. 29, 2017	Dec. 30, 2016	Dec. 25, 2015
Shares
Outstanding (in shares)		209,071	0
Granted (in shares)	259,577	0	259,577
Exercised (in shares)		0	0
Forfeited (in shares)		(17,263)	(50,506)
Outstanding (in shares)		191,808	209,071
Exercisable (in shares)		0
Weighted Average Exercise Price
Outstanding (in usd per share)		$ 20.23	$ 0.00
Granted (in usd per share)	$ 20.23	0.00	20.23
Exercised (in usd per share)		0.00	0.00
Forfeited (in usd per share)		20.23	20.23
Outstanding (in usd per share)		20.23	$ 20.23
Exercisable (in usd per share)		$ 0.00
Aggregate Intrinsic Value
Outstanding		$ 33	$ 0	$ 0
Exercisable		$ 0
Weighted Average Remaining Contractual Term (in years)
Outstanding		8 years 2 months 12 days	9 years 2 months