Benefit Plans - Pension Plans Resulted in Net Pension Liability (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Prepaid pension assets	$ 516	$ 132
Other current liabilities	(35)	(25)
Accrued pension costs	(1,190)	(1,221)
Total	(709)	(1,114)
Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Total	(709)	(1,114)
Pension Plans | U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	55	52
Accumulated benefit obligation	55	50
Fair value of plan assets	2	2
Pension Plans | Non-U.S. Plans
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	3,613	3,343
Accumulated benefit obligation	3,447	3,194
Fair value of plan assets	$ 2,443	$ 2,169