Earnings Per Share (EPS) And Dividends (Dividend Payments On Common Stock) (Detail) (USD $) In Millions, except Per Share data, unless otherwise specified	12 Months Ended	0 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 17, 2015
Earnings Per Share, Diluted [Line Items]
Dividend Payments on Common Stock, Per Share	$ 1.48	$ 1.44	$ 1.42
Dividend Payments on Common Stock	$ 748us-gaap_PaymentsOfDividendsCommonStock	$ 728us-gaap_PaymentsOfDividendsCommonStock	$ 718us-gaap_PaymentsOfDividendsCommonStock
Subsequent Event [Member]
Earnings Per Share, Diluted [Line Items]
Common stock dividends per share				$ 0.39

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

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- Definition

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

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Financing Activities

-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 15

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3291-108585

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