Shareholders' Equity - Schedule of Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019
Equity, Class of Treasury Stock [Line Items]
Cash dividends declared (in USD per share)	$ 0.52	$ 0.52
Total (In millions)	$ 182	$ 183
2019 Program
Equity, Class of Treasury Stock [Line Items]
Shares Acquired (in shares)	6.2	6.5
Average Cost per Share (USD per share)	$ 76.21	$ 77.35
Total Acquired	$ 475	$ 500	$ 500	$ 500

Aggregate dividends declared during the period for each share of common stock outstanding.

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Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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