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, 2019	Mar. 31, 2019	Mar. 31, 2018
Common Stock, Dividends, Per Share, Cash Paid		$ 0.47	$ 0.45
Dividend Payments on Common Stock		$ 238	$ 227
Subsequent Event [Member]
Common Stock, Dividends, Per Share, Declared	$ 0.47

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
-Paragraph 1
-Subparagraph (SX 210.3-04)
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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.

+ References

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)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3291-108585

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