Pension and Other Postretirement Benefit Plans - Defined Contribution Plans (Details) $ in Thousands	9 Months Ended
Jun. 26, 2020 USD ($)
Retirement Benefits [Abstract]
Cash contributions made during the first nine months of fiscal 2020	$ 19,694
Cash contributions projected for the remainder of fiscal 2020	7,135
Total	$ 26,829

Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3536-108585

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