Fair Value Measurements - Carrying Value and Estimated Fair Value of Notes (Details) - Senior Notes - USD ($) $ in Thousands	Jan. 17, 2021	Sep. 27, 2020
Series 2019-1 Variable Funding Senior Secured Notes, Class A-1
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Notes	$ 107,900
Carrying Amount \| Class A-2 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	1,290,251	$ 1,290,251
Fair Value \| Class A-2 Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total debt	$ 1,354,188	$ 1,354,241

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant