Franchises, Goodwill and Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Indefinite-lived Intangible Assets:
Goodwill	$ 29,554		$ 29,554		$ 29,509
Indefinite-lived intangible assets and goodwill	97,029		97,029		96,988
Finite-lived Intangible Assets:
Gross carrying amount	18,891		18,891		18,841
Accumulated Amortization	(5,158)		(5,158)		(3,746)
Net Carrying Amount	13,733		13,733		15,095
Amortization expense	695	$ 403	1,400	$ 464
Six months ended December 31, 2017	1,327		1,327
2018	2,468		2,468
2019	2,185		2,185
2020	1,894		1,894
2021	1,609		1,609
Thereafter	4,250		4,250
Franchises [Member]
Indefinite-lived Intangible Assets:
Indefinite-lived intangible assets	67,316		67,316		67,316
Trademarks [Member]
Indefinite-lived Intangible Assets:
Indefinite-lived intangible assets	159		159		159
Other Intangible Assets [Member]
Indefinite-lived Intangible Assets:
Indefinite-lived intangible assets	0		0		4
Customer Relationships [Member]
Finite-lived Intangible Assets:
Gross carrying amount	18,227		18,227		18,226
Accumulated Amortization	(4,996)		(4,996)		(3,618)
Net Carrying Amount	13,231		13,231		14,608
Other Intangible Assets [Member]
Finite-lived Intangible Assets:
Gross carrying amount	664		664		615
Accumulated Amortization	(162)		(162)		(128)
Net Carrying Amount	$ 502		$ 502		$ 487