Derivative financial instruments - Fair Values of Derivative Instruments (Details) - USD ($) $ in Millions	Apr. 02, 2022	Jan. 01, 2022
Derivatives, Fair Value
Net	$ (7.9)	$ (51.4)
Prepaid expenses and other assets
Derivatives, Fair Value
Derivative assets	14.6	2.9
Other non- current assets
Derivatives, Fair Value
Derivative assets	33.4	7.7
Accrued expenses and other current liabilities
Derivatives, Fair Value
Derivative liabilities	(12.3)	(34.6)
Other non- current liabilities
Derivatives, Fair Value
Derivative liabilities	(43.6)	(27.4)
Derivatives designated as hedging instruments: | —Currency swaps
Derivatives, Fair Value
Net	(14.3)	(19.8)
Derivatives designated as hedging instruments: | —Currency swaps | Prepaid expenses and other assets
Derivatives, Fair Value
Derivative assets	5.1	0.0
Derivatives designated as hedging instruments: | —Currency swaps | Accrued expenses and other current liabilities
Derivatives, Fair Value
Derivative liabilities	0.0	19.8
Derivatives designated as hedging instruments: | —Currency swaps | Other non- current liabilities
Derivatives, Fair Value
Derivative liabilities	(19.4)	0.0
Derivatives designated as hedging instruments: | —Interest rate caps
Derivatives, Fair Value
Net	(1.2)	(1.8)
Derivatives designated as hedging instruments: | —Interest rate caps | Accrued expenses and other current liabilities
Derivatives, Fair Value
Derivative liabilities	(1.2)	(1.3)
Derivatives designated as hedging instruments: | —Interest rate caps | Other non- current liabilities
Derivatives, Fair Value
Derivative liabilities	0.0	(0.5)
Derivatives designated as hedging instruments: | —Interest rate swaps
Derivatives, Fair Value
Net	4.3	(32.1)
Derivatives designated as hedging instruments: | —Interest rate swaps | Prepaid expenses and other assets
Derivatives, Fair Value
Derivative assets	5.8
Derivatives designated as hedging instruments: | —Interest rate swaps | Other non- current assets
Derivatives, Fair Value
Derivative assets	33.4	7.7
Derivatives designated as hedging instruments: | —Interest rate swaps | Accrued expenses and other current liabilities
Derivatives, Fair Value
Derivative liabilities	(10.7)	(12.9)
Derivatives designated as hedging instruments: | —Interest rate swaps | Other non- current liabilities
Derivatives, Fair Value
Derivative liabilities	(24.2)	(26.9)
Derivatives not designated as hedging instruments: | —Currency forward contracts
Derivatives, Fair Value
Net	3.3	2.3
Derivatives not designated as hedging instruments: | —Currency forward contracts | Prepaid expenses and other assets
Derivatives, Fair Value
Derivative assets	3.7	2.9
Derivatives not designated as hedging instruments: | —Currency forward contracts | Accrued expenses and other current liabilities
Derivatives, Fair Value
Derivative liabilities	$ (0.4)	$ (0.6)