Supplemental Cash Flow Disclosures (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Supplemental Cash Flow Information [Abstract]
Cash and cash equivalents		$ 1,290	$ 1,040
Restricted cash and cash equivalents		140	212
Restricted Cash and Cash Equivalents, Noncurrent		15	16
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents		1,445	1,268	$ 883	$ 1,283
Interest paid, net of amounts capitalized		1,855	1,723	1,713
Income Taxes Paid, Net	[1]	(1,361)	(850)	(780)
Capital Expenditures Incurred but Not yet Paid		801	888	823
Related Party Transaction, Cash Received for Income Taxes, Net		$ 1,504	$ 942	$ 884

[1] Includes $1,504 million, $942 million and $884 million of income taxes received from Berkshire Hathaway in 2020, 2019 and 2018, respectively.