Significant Accounting Policies - Basis of Presentation (Details)	9 Months Ended	12 Months Ended
Sep. 29, 2020	Dec. 31, 2019	Oct. 29, 2020
Significant Accounting Policies
Length of fiscal year	364 days	364 days
Operating capacity of reopened dinning rooms (in percentage)			50.00%

Duration of a fiscal period, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Includes, but not limited to, weeks in a year or quarter.

No definition available.

Name:	us-gaap_FiscalPeriodDuration
Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration