Capital Stock (Schedule of Shares Repurchased) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended			24 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2022
Class of Stock [Line Items]
Total number of shares repurchased (in shares)	22,748,842	38,156,312	35,656,116
Aggregate cost of shares repurchased	$ 1,000	$ 1,825	$ 1,675
January 2023 Share Repurchase Program [Member]
Class of Stock [Line Items]
Total number of shares repurchased (in shares)	22,700,000
Aggregate cost of shares repurchased	$ 1,000
Average price per share of shares repurchased (USD per share)	$ 43.96
January 2021 Share Repurchase Program [Member]
Class of Stock [Line Items]
Total number of shares repurchased (in shares)		38,100,000	35,700,000	73,800,000
Aggregate cost of shares repurchased		$ 1,825	$ 1,675	$ 3,500
Average price per share of shares repurchased (USD per share)		$ 47.83	$ 46.97	$ 47.42