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Retirement and Post Retirement Health Care Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Jan. 02, 2021	Dec. 28, 2019	Dec. 29, 2018	Dec. 21, 2026
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Net actuarial losses	$ 24.1	$ 37.0
Discount rates and census experience	2.9	2.1
Accumulated benefit obligation	$ 292.8	$ 276.3
Defined benefit plan compensation increase assumption	3.00%	3.00%
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	$ 8.5	$ 10.8
Funded status of plan	(68.2)	(79.4)
Expected contribution to defined benefit pension plans	5.3
Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	0.3	0.4
Expected contribution to defined benefit pension plans	0.5
Postretirement Health Coverage \| Forecast
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Health care cost trend rate, 2031				4.50%
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	7.6	8.9	$ 10.1
United States \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Funded status of plan	(62.6)	(71.2)
International Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	5.5	10.6	$ 11.8
International Plan \| Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Funded status of plan	$ (5.6)	$ (8.2)
Pre-65 \| Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Health care cost trend rate, next fiscal year	5.80%	6.80%	7.60%
Post-65 \| Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Health care cost trend rate, next fiscal year	5.60%	5.10%	5.30%