Related party transactions - Transactions with Non-Gates entities (Details) - Non-Gates entities controlled by non-controlling shareholders - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019	Dec. 28, 2019
Related Party Transaction
Sales	$ 12.0	$ 12.4	$ 24.5	$ 25.8
Purchases	(4.2)	$ (4.9)	(9.3)	$ (10.3)
Receivables	3.8		3.8		$ 4.2
Payables	$ (3.2)		$ (3.2)		$ (5.9)

For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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Carrying amount as of the balance sheet date of obligations due all related parties.

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Purchases during the period (excluding transactions that are eliminated in consolidated or combined financial statements) with related party.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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