Fair Value Measurements Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 27, 2020	Dec. 29, 2019
Reported Value Measurement
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash equivalents	$ 75,062	$ 114,992
Other investments in equity securities	0	639
Reported Value Measurement \| Series 2019-1 Class A-2-I Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	391,000	398,000
Reported Value Measurement \| Series 2019-1 Class A-2-II Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	439,875	447,750
Reported Value Measurement \| Series 2018-1 Class A-2-I Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	437,625	441,000
Reported Value Measurement \| Series 2018-1 Class A-2-II Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	461,938	465,500
Reported Value Measurement \| Series 2015-1 Class A-2-III Notes
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	475,000	478,750
Reported Value Measurement \| Canadian revolving credit facility
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	4,108	0
Reported Value Measurement \| 7% Debentures
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	83,696	82,837
Estimate of Fair Value Measurement \| Fair Value, Inputs, Level 1
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Cash equivalents	75,062	114,992
Estimate of Fair Value Measurement \| Fair Value, Inputs, Level 3
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Other investments in equity securities	0	1,649
Estimate of Fair Value Measurement \| Series 2019-1 Class A-2-I Notes \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	414,499	405,152
Estimate of Fair Value Measurement \| Series 2019-1 Class A-2-II Notes \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	477,792	459,136
Estimate of Fair Value Measurement \| Series 2018-1 Class A-2-I Notes \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	452,198	444,859
Estimate of Fair Value Measurement \| Series 2018-1 Class A-2-II Notes \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	491,641	475,718
Estimate of Fair Value Measurement \| Series 2015-1 Class A-2-III Notes \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	486,543	490,531
Estimate of Fair Value Measurement \| Canadian revolving credit facility \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	4,108	0
Estimate of Fair Value Measurement \| 7% Debentures \| Fair Value, Inputs, Level 2
Fair Value, Balance Sheet Grouping, Financial Statement Captions
Debt instrument	$ 98,100	$ 94,838

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

No definition available.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611

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- Definition

Amount of investment in equity security without readily determinable fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=116654751&loc=SL75117539-209714

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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