Fair value measurement - Carrying Amount and Fair Value of Debt (Details) - USD ($) $ in Millions	Dec. 30, 2023	Dec. 31, 2022
Carrying amount
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Current	$ 36.5	$ 36.6
Non-current	2,415.0	2,426.4
Fair value of debt	2,451.5	2,463.0
Fair value
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis
Current	36.5	36.2
Non-current	2,444.7	2,408.4
Fair value of debt	$ 2,481.2	$ 2,444.6

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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69B

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
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-Name Accounting Standards Codification
-Section 55
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-URI https://asc.fasb.org//1943274/2147481568/470-20-55-69C

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
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-Publisher FASB
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-10

Name:	us-gaap_DebtInstrumentFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant