Supplemental Equity and Comprehensive Income Information - Reclass AOCI (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Amount Reclassified from Accumulated Other Comprehensive Income
Net of tax	$ (107)	$ (78)
Defined Pension and Postretirement Plans Adjustment
Amount Reclassified from Accumulated Other Comprehensive Income
Transition asset	(1)
Prior service benefit	15	16
Net actuarial loss	(177)	(120)
Curtailments/Settlements	(1)
Total before tax	(164)	(104)
Tax effect	45	20
Net of tax	(119)	(84)
Cash Flow Hedging Instruments, Unrealized Gain (Loss)
Amount Reclassified from Accumulated Other Comprehensive Income
Total before tax	16	7
Tax effect	(4)	(1)
Net of tax	12	6
Cash Flow Hedging Instruments, Unrealized Gain (Loss) | Foreign currency forward/option contracts
Amount Reclassified from Accumulated Other Comprehensive Income
Cost of sales	18	$ 7
Cash Flow Hedging Instruments, Unrealized Gain (Loss) | Interest rate contracts
Amount Reclassified from Accumulated Other Comprehensive Income
Interest expense	$ (2)