Stock Compensation - Expense (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation	$ 217	$ 232	$ 242
COR
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation	21	25	36
R&D
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation	66	69	59
SG&A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock compensation	$ 130	$ 138	$ 147