Long-term debt: - Limitations under the Indentures (Details)	9 Months Ended
Sep. 30, 2026 USD ($)	Sep. 29, 2026
Long-term debt
Amount unrestricted and permitted for investment payments	$ 289,500,000
Minimum
Long-term debt
Consolidated secured leverage ratio	1	1
Maximum
Long-term debt
Consolidated secured leverage ratio	4.75	4
Indentures \| Minimum
Long-term debt
Consolidated leverage ratio	1
Fixed charge coverage ratio	1
Consolidated secured leverage ratio	1
Indebtedness that may occur	$ 1
Indentures \| Maximum
Long-term debt
Consolidated leverage ratio	6
Fixed charge coverage ratio	2
Consolidated secured leverage ratio	4
2027 Notes Indentures \| Minimum
Long-term debt
Consolidated leverage ratio	1
Fixed charge coverage ratio	2
2027 Notes Indentures \| Maximum
Long-term debt
Consolidated leverage ratio	6
Consolidated secured leverage ratio	4
2032 Notes Indenture
Long-term debt
Consolidated secured leverage ratio	4
2032 Notes Indenture \| Minimum
Long-term debt
Consolidated leverage ratio	1
Fixed charge coverage ratio	2
Consolidated secured leverage ratio	1
2032 Notes Indenture \| Maximum
Long-term debt
Consolidated leverage ratio	6
Consolidated secured leverage ratio	4.75

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.

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