v2.4.0.8

Share-Based Compensation (Narrative) (Details) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013
Stock Options [Member] |
Unrecognized pretax compensation expense on nonvested awards | $ 318
Unrecognized pretax compensation expense on nonvested awards, weighted average period of recognition (in years) | 1 year 10 months 24 days
Stock Options [Member] | NBCUniversal Media, LLC [Member] |
Unrecognized pretax compensation expense on nonvested awards | 35
Unrecognized pretax compensation expense on nonvested awards, weighted average period of recognition (in years) | 2 years 2 months 12 days
Restricted Share Units [Member] |
Unrecognized pretax compensation expense on nonvested awards | 380
Unrecognized pretax compensation expense on nonvested awards, weighted average period of recognition (in years) | 1 year 8 months 12 days
Restricted Share Units [Member] | NBCUniversal Media, LLC [Member] |
Unrecognized pretax compensation expense on nonvested awards | $ 98
Unrecognized pretax compensation expense on nonvested awards, weighted average period of recognition (in years) | 1 year 8 months 12 days

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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 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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- Definition 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. + 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 + Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration