Commitments and Contingencies (Details) $ in Millions			3 Months Ended				9 Months Ended		12 Months Ended
	Aug. 02, 2020 USD ($)	Mar. 14, 2019 USD ($)	Jan. 01, 2021 USD ($)	Sep. 25, 2020 USD ($)	Dec. 27, 2019 USD ($)	Sep. 27, 2019 USD ($)	Sep. 25, 2020 USD ($)	Sep. 27, 2019 USD ($)	Dec. 31, 1980 subsidiary
Commitments and Contingencies Disclosure [Line Items]
Award from litigation settlement		$ 17.0
Gain on litigation settlement		16.0
Litigation expense		$ 1.0
Restructuring, Settlement and Impairment Provisions				$ (3.5)		$ 4.7	$ (3.8)	$ 8.5
Asset impairments				0.1		4.7	2.9	8.0
Estimated Litigation Liability, Current	$ 1.0
Non-compliance with regulations
Commitments and Contingencies Disclosure [Line Items]
Award from litigation settlement	2.0
Estimated Litigation Liability, Current	$ 1.0
Kunia Well Site
Commitments and Contingencies Disclosure [Line Items]
Number of plaintiffs | subsidiary									1
Kunia Well Site cleanup operation, undiscounted estimated remediation costs associated with the cleanup				13.2			13.2
Accrual for environmental loss contingencies, undiscounted, due within one year				0.4			0.4
Accrual for environmental loss contingencies, undiscounted, due in second year				1.1			1.1
Accrual for environmental loss contingencies, undiscounted, due in third year				0.9			0.9
Accrual for environmental loss contingencies, undiscounted, due in fourth year				0.9			0.9
Accrual for environmental loss contingencies, undiscounted, due in fifth year				0.9			0.9
Kunia Well Site | Other noncurrent liabilities
Commitments and Contingencies Disclosure [Line Items]
Kunia Well Site cleanup operation, accrual for the expected future clean-up costs				12.9			12.9
Kunia Well Site | Accounts payable and accrued expenses
Commitments and Contingencies Disclosure [Line Items]
Kunia Well Site cleanup operation, accrual for the expected future clean-up costs				0.3			0.3
Kunia Well Site | Minimum
Commitments and Contingencies Disclosure [Line Items]
Kunia Well Site cleanup operation, undiscounted estimated remediation costs associated with the cleanup				13.2			13.2
Kunia Well Site | Maximum
Commitments and Contingencies Disclosure [Line Items]
Kunia Well Site cleanup operation, undiscounted estimated remediation costs associated with the cleanup				28.7			28.7
Net Sales | Mann Packing
Commitments and Contingencies Disclosure [Line Items]
Loss Contingency, Loss in Period					$ 6.0
Cost of products sold | Mann Packing
Commitments and Contingencies Disclosure [Line Items]
Loss Contingency, Loss in Period					$ 4.4
Non-compliance with regulations
Commitments and Contingencies Disclosure [Line Items]
Restructuring, Settlement and Impairment Provisions							2.0
Fresh and value-added products
Commitments and Contingencies Disclosure [Line Items]
Restructuring, Settlement and Impairment Provisions				0.0		0.0	2.1	0.4
Asset impairments				0.0		$ 0.0	2.1	$ 0.4
Fresh and value-added products | Non-compliance with regulations
Commitments and Contingencies Disclosure [Line Items]
Restructuring, Settlement and Impairment Provisions				0.0			0.7
Fresh and value-added products | Vegetable Product Recall [Member]
Commitments and Contingencies Disclosure [Line Items]
Restructuring Charges (Credits)							10.4
Asset impairments				0.0			0.0
Fresh and value-added products | Vegetable Product Recall [Member] | Subsequent Event
Commitments and Contingencies Disclosure [Line Items]
Restructuring Charges (Credits)			$ 4.6
Banana | Non-compliance with regulations
Commitments and Contingencies Disclosure [Line Items]
Restructuring, Settlement and Impairment Provisions				0.0			1.3
Asset impairments				$ 0.0			$ 0.0