Commitments and Contingencies (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 30, 2017	Jul. 01, 2017
Commitments and Contingencies Disclosure [Abstract]
Purchase Obligation, Due in Next Twelve Months	$ 30,000
Purchase Obligation, Due Second Year	0
Letters of Credit Outstanding, Amount	$ 39,900	$ 39,600	$ 44,300

Minimum amount of purchase arrangement maturing in the next fiscal year following the latest fiscal year. Includes, but not limited to, recorded and unrecorded purchase obligations, long-term purchase commitments, and short-term purchase commitments.

No definition available.

Name:	us-gaap_PurchaseObligationDueInNextTwelveMonths
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant