Cash, Cash Equivalents and Restricted Cash - Schedule of Cash, Cash Equivalents and Restricted Cash (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017	Dec. 30, 2017	Apr. 01, 2017	Dec. 31, 2016
Cash and Cash Equivalents [Abstract]
Cash and cash equivalents	$ 6,767		$ 8,988
Restricted cash			660
Total cash, cash equivalents and restricted cash	$ 6,767	$ 9,648	$ 9,648	$ 14,373	$ 15,687