Intangible Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 15,296	$ 15,271	$ 15,541
Other intangible assets	6,100	6,100
Intangible assets subject to amortization	3,200	3,200
Intangible assets not subject to amortization	2,900	2,900
Amortization of Purchased Intangibles	$ 305	$ 339	$ 260