Aggregate number of common shares reserved for future issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Unrecognized cost of unvested share-based compensation awards.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Disclosure of the aggregate tax benefit realized from the exercise of stock options and the conversion of similar instruments during the annual period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (j)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Represents the quantification of the effect of adopting the new accounting standard or change in accounting principle expected by the entity to have a significant effect on the entity's financial statements.

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No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Stock Transactions And Stock-Based Compensation (Narrative) (Details) - USD ($) shares in Millions, $ in Millions		3 Months Ended
	Mar. 31, 2017	Mar. 31, 2017	Apr. 01, 2016	Jul. 16, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock repurchase program, authorized shares to be repurchased, shares				20
Stock repurchase program, remaining number of shares authorized to be repurchased, shares	20	20
Common shares reserved for issuance under the 2007 Stock Incentive Plan, shares	23	23
Tax benefit realized related to exercise of options		$ 38
New accounting pronouncement, effect of adoption, compensation-stock compensation		26	$ 14
Restricted stock units (“RSUs”)/performance stock units (“PSUs”)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$ 208	208
Weighted average period for cost to be recognized	3 years
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total unrecognized compensation cost	$ 159	$ 159
Weighted average period for cost to be recognized	3 years