Employee Benefit Plans Employee Benefit Plans Narrative 3 (Details) $ in Thousands	12 Months Ended
Dec. 28, 2019 USD ($) plan	Dec. 29, 2018 USD ($)	Dec. 30, 2017 USD ($)
Employee Benefit Plans [Abstract]
Number of Multiemployer Plans, Certified Red Zone	5
Number Of Multiemployer Plans, Withdrawal Obligation Could Be Material	2
Number of Multiemployer Plans, Certified Yellow Zone	2
Contributions \| $	$ 3,626	$ 3,547	$ 3,472
Multiemployer Plans, Withdrawal Obligation \| $	$ 6,000

Amount of contributions made to multiemployer plan by employer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 9
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 80
-Section 50
-Paragraph 5
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947

Name:	us-gaap_MultiemployerPlanContributionsByEmployer
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration