Stockholders' Equity (Summary of Purchases of Common Stock) (Details) - 1.6 Billion Dollar Share Repurchase Program Open [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2022	Dec. 31, 2021	Mar. 31, 2022
Stockholders Equity [Line Items]
Total Number of Shares Purchased	3,979	13,983	17,962
Dollar Value of Shares Purchased	$ 230	$ 589	$ 819
Average Price Paid per Share	$ 57.74	$ 42.15	$ 45.61

Equity impact of the value of stock that has been repurchased and retired during the period. The excess of the purchase price over par value can be charged against retained earnings (once the excess is fully allocated to additional paid in capital).

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