Acquisitions, Dispositions, Goodwill and Other Intangible Assets (Intangible Assets) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2019
Finite-Lived Intangible Assets [Line Items]
Gross Amount	$ 30,426	$ 30,533
Accumulated Amortization	8,634	8,403
Unamortized: Trademarks and Other	3,808	3,916
Total Intangible Assets Gross Excluding Goodwill	34,234	34,449
Impairment of Intangible Asset, Tradename	40
Service portfolios [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	2,052	2,105
Accumulated Amortization	1,600	1,626
Patents and trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	350	356
Accumulated Amortization	249	250
Collaboration intangible assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	4,940	4,862
Accumulated Amortization	990	920
Customer relationships and other [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Amount	23,084	23,210
Accumulated Amortization	$ 5,795	$ 5,607