Employee Retirement Plans (International Defined Benefit Plan Assets) (Details) - Pension Benefits [Member] - International [Member] - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Insurance Contracts [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 2	$ 2
Insurance Contracts [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	2	2
Collateralized Mortgage Backed Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	22
Collateralized Mortgage Backed Securities [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	21	22
Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	40	45
Cash Equivalents [Member] | Quoted Market Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	40	45
Defined Benefit Plans Assets [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	518	497
Defined Benefit Plans Assets [Member] | Quoted Market Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	413	406
Defined Benefit Plans Assets [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	82	67
Defined Benefit Plans Assets [Member] | Significant Unobservable Inputs (Level 3) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23	24
International Companies [Member] | Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	455	428
International Companies [Member] | Fixed Income Securities [Member] | Quoted Market Prices in Active Markets for Identical Assets (Level 1) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	373	361
International Companies [Member] | Fixed Income Securities [Member] | Significant Other Observable Inputs (Level 2) [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 82	$ 67