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Retirement and Post Retirement Health Care Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017	Dec. 21, 2026
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	$ 10.8	$ 10.9
Accumulated benefit obligation	$ 276.3	$ 244.0
Defined benefit plan compensation increase assumption	3.00%	3.00%
Expected contribution to defined benefit pension plans	$ 10.1
Pension Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	10.8	$ 10.9
Future amortization of prior service cost	0.3
Amount to be amortized	1.8
Postretirement Health Coverage
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	0.4	0.6
Future amortization of prior service cost	0.9
Net actuarial gain expected amortization	0.6
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, 2026				4.50%
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	8.9	10.1	$ 9.3
International Plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Employer Contributions	$ 10.6	$ 11.8	$ 9.4
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	6.80%
Health care cost trend rate, 2026	7.60%	8.00%
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	5.10%
Health care cost trend rate, 2026	5.30%	5.40%