EMPLOYEE BENEFIT PLANS - Projected Benefit Obligation and Fair Value of Plan Assets for Pension Plans with Projected Benefit Obligations in Excess of Plan Assets (Details) - USD ($) $ in Thousands	Dec. 26, 2020	Dec. 28, 2019
Retirement Benefits [Abstract]
Projected benefit obligation	$ 93,192	$ 435,638
Fair value of plan assets	$ 18,560	$ 343,688

Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2417-114920

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