Significant accounting policies - Financial liabilities (Details) - vessel		12 Months Ended
Dec. 30, 2019	Dec. 31, 2021
Disclosure of detailed information about borrowings [line items]
Number of bareboat-in vessels		3
Sale and leaseback agreement
Disclosure of detailed information about borrowings [line items]
Number of bareboat-in vessels	3

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

No definition available.

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