Shareholders' Equity - Schedule of Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended						12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Equity, Class of Treasury Stock [Line Items]
Total Acquired	$ 0	$ 0	$ 0
Cash dividends declared (in USD per share)							$ 2.18	$ 2.08	$ 1.98
Total (In millions)							$ 779	$ 734	$ 728
2019 Program
Equity, Class of Treasury Stock [Line Items]
Shares Acquired (in shares)							11.2	6.5
Average Cost per Share (USD per share)							$ 80.00	$ 77.35
Total Acquired				$ 500	$ 500	$ 500	$ 900	$ 500