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

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Amount of paid and unpaid common stock dividends declared with the form of settlement in cash.

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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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Shareholders' Equity - Schedule of Common Stock (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended								6 Months Ended
	Jun. 30, 2021	Mar. 31, 2021	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2021	Jun. 30, 2020
Equity, Class of Treasury Stock [Line Items]
Cash dividends declared (in USD per share)	$ 0.52	$ 0.52			$ 0.52	$ 0.52			$ 1.04	$ 1.04
Total (In millions)	$ 179	$ 182			$ 183	$ 183			$ 361	$ 366
2019 Program
Equity, Class of Treasury Stock [Line Items]
Shares Acquired (in shares)	5.0				0.0				11.2	6.5
Average Cost per Share (USD per share)	$ 84,710,000				$ 0				$ 80.00	$ 77.35
Total Acquired	$ 425		$ 0	$ 0	$ 0	$ 500	$ 500	$ 500	$ 900	$ 500