Earnings Per Share (EPS) And Dividends (Dividend Payments On Common Stock) (Detail) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended
Apr. 30, 2021	Mar. 31, 2021	Mar. 31, 2020
Common Stock, Dividends, Per Share, Cash Paid		$ 0.51	$ 0.49
Dividend Payments on Common Stock		$ 258	$ 248
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.51

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
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Aggregate dividends declared during the period for each share of common stock outstanding.

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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
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