Short-term and Long-term Debt - Summary (Detail) - USD ($) $ in Millions	Sep. 26, 2020	Apr. 30, 2020	Dec. 28, 2019
Schedule Of Debt Instruments [Line Items]
Long term debt	$ 1,449.7		$ 1,149.8
Less: notes payable and current maturities of long-term debt
Current maturities of long-term debt	(250.0)		0.0
Total current debt	(267.9)		(202.9)
Total long-term debt	1,181.8		946.9
Commercial paper borrowings
Less: notes payable and current maturities of long-term debt
Short-term debt	0.0		(193.6)
Other notes
Less: notes payable and current maturities of long-term debt
Short-term debt	(17.9)		(9.3)
Other Debt
Schedule Of Debt Instruments [Line Items]
Long term debt	$ (0.3)		199.8
6.125% unsecured notes due 2021
Schedule Of Debt Instruments [Line Items]
Unsecured notes, interest rate	6.125%
6.125% unsecured notes due 2021 | Unsecured Debt
Schedule Of Debt Instruments [Line Items]
Long term debt	$ 250.0		250.0
3.25% unsecured notes due 2027
Schedule Of Debt Instruments [Line Items]
Unsecured notes, interest rate	3.25%
3.25% unsecured notes due 2027 | Unsecured Debt
Schedule Of Debt Instruments [Line Items]
Long term debt	$ 300.0		300.0
4.10% unsecured notes due 2048
Schedule Of Debt Instruments [Line Items]
Unsecured notes, interest rate	4.10%
4.10% unsecured notes due 2048 | Unsecured Debt
Schedule Of Debt Instruments [Line Items]
Long term debt	$ 400.0		400.0
3.10% unsecured notes due 2050
Schedule Of Debt Instruments [Line Items]
Unsecured notes, interest rate	3.10%
3.10% unsecured notes due 2050 | Unsecured Debt
Schedule Of Debt Instruments [Line Items]
Unsecured notes, interest rate		3.10%
Long term debt	$ 500.0		$ 0.0