UNAUDITED CONDENSED CONSOLIDATED BALANCE SHEETS (Parenthetical) - shares shares in Thousands	Jun. 27, 2021	Dec. 31, 2020	Jun. 28, 2020
Statement of Financial Position [Abstract]
Limited partners, units outstanding (in shares)	56,829	56,706	56,707

The number of limited partner units outstanding.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 5
-Subparagraph (SAB Topic 4.F)
-URI http://asc.fasb.org/extlink&oid=120397183&loc=d3e187171-122770

Name:	us-gaap_LimitedPartnersCapitalAccountUnitsOutstanding
Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant