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Pension Plans and Other Postretirement Benefits (Narrative) (Details)		12 Months Ended
	Jan. 01, 2021	Dec. 31, 2020 USD ($) plans	Dec. 31, 2019 USD ($)	Dec. 31, 2018
Pension Benefits | United States
Defined Benefit Plan Disclosure [Line Items]
Number of pension plans | plans		4
Defined Benefit Plan, Accumulated Benefit Obligation		$ 392,000,000	$ 346,000,000
Expected long-term rate of return on plan assets	8.00%	8.50%	8.50%	8.50%
Number of business days notice required to make withdrawals		10 days
Estimated contributions to defined benefit plans in next fiscal year		$ 3,000,000
Pension Benefits | United States | Debt Securities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		3.00%
Pension Benefits | United States | Debt Securities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		10.00%
Pension Benefits | United States | Equities | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		90.00%
Pension Benefits | United States | Equities | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		97.00%
Pension Benefits | United States | Pooled Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 0
Pension Benefits | United States | Cash and cash equivalents | Minimum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		1.00%
Pension Benefits | United States | Cash and cash equivalents | Maximum
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		5.00%
Pension Benefits | Foreign Retirement Plans
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Accumulated Benefit Obligation		$ 224,000,000	$ 171,000,000
Expected long-term rate of return on plan assets		5.23%	5.58%	5.50%
Estimated contributions to defined benefit plans in next fiscal year		$ 7,000,000
Pension Benefits | Foreign Retirement Plans | Debt Securities | Pooled Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		37.00%
Pension Benefits | Foreign Retirement Plans | Equities | Pooled Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		38.00%
Pension Benefits | Foreign Retirement Plans | Insurance contract
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		6.00%
Pension Benefits | Foreign Retirement Plans | Pooled investment funds Diversified growth funds
Defined Benefit Plan Disclosure [Line Items]
Target allocation percentage for plan assets		19.00%
Pension Benefits | UNITED KINGDOM | Pooled Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 0
Pension Benefits | CANADA | Pooled Investment Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair Value, Investments, Entities that Calculate Net Asset Value Per Share, Unfunded Commitments		$ 0
Postretirement Benefits | United States
Defined Benefit Plan Disclosure [Line Items]
Expected long-term rate of return on plan assets		4.50%	4.50%	4.50%
Estimated contributions to defined benefit plans in next fiscal year		$ 2,000,000

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Amount of actuarial present value of benefits attributed to employee service rendered, excluding assumptions about future compensation level.

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Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

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