Financing Activities Financing Activities- Equity Securities (Details) - USD ($) shares in Thousands, $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Aug. 01, 2021	Feb. 28, 2018
Equity Programs [Line Items]
Issuance of common stock		$ 9	$ 34	$ 1,167
Stock Repurchase Program, Authorized Amount					$ 3,000
Treasury Stock, Value, Acquired, Cost Method		$ 1,003
Common Stock [Member]
Equity Programs [Line Items]
Common stock shares issued	[1]	983	1,674	46,910
Treasury stock		(34,778)
Treasury Stock
Equity Programs [Line Items]
Treasury Stock, Value, Acquired, Cost Method		$ (1,003)
At The Market Stock Offering Program [Member]
Equity Programs [Line Items]
Common Stock Aggregate Sales Price						$ 1,000
Maximum Percentage Paid To Selling Agents		2.00%
Common stock shares issued		0	0

[1] Shares in thousands. Each share entitles the holder to one vote on any question presented at any shareowners' meeting.