v2.4.0.8

Long-Term Debt (Narrative) (Details) (USD $) | 9 Months Ended
--- | ---
Sep. 30, 2014 | Sep. 30, 2013
Total debt | $ 48,400,000,000 |
Long-term Debt, Fair Value | 54,400,000,000 |
Amounts available under revolving credit facilities | 6,400,000,000 |
Repurchases and repayments of debt | 3,172,000,000 | 2,442,000,000
Comcast ownership in cable holding company subsidiaries | 100.00% |
Proceeds from (repayments of) short-term borrowings, net | (437,000,000) | 395,000,000
NBCUniversal Media, LLC [Member] |  |
Total debt | 10,300,000,000 |
Long-term Debt, Fair Value | 11,300,000,000 |
Comcast ownership in cable holding company subsidiaries | 100.00% |
Related Party Aggregate Principal Amount Senior Notes Not Subject To Guarantee | 4,000,000,000 |
Related Party Credit Facility Not Subject To Guarantee | 1,350,000,000 |
Related Party Liquidation Preference Preferred Stock Not Subject To Guarantee | 725,000,000 |
NBCUniversal Enterprise Commercial Paper [Member] |  |
Credit facility borrowing capacity | 1,350,000,000 |
Commercial paper | 910,000,000 |
Proceeds from (repayments of) short-term borrowings, net | 990,000,000 |
Comcast And Comcast Cable Revolving Credit Facility [Member] | NBCUniversal Media, LLC [Member] |  |
Debt Instrument, Maturity Date, Description | 2017 |
Guarantee Obligations Revolving Credit Facility | 6,250,000,000 |
Comcast And Comcast Cable Debt Securities [Member] | NBCUniversal Media, LLC [Member] |  |
Guarantee Obligations Current Principal Balance | 32,600,000,000 |
NBCUniversal Enterprise Credit Facility [Member] |  |
Debt Instrument, Maturity Date, Description | March 2018 |
Credit facility borrowing capacity | 1,350,000,000 |
Amounts available under revolving credit facilities | 440,000,000 |
Repurchases and repayments of debt | 1,250,000,000 |
Senior 3.60% Notes Due 2024 [Member] |  |
Principal amount | 1,200,000,000 |
Interest rate | 3.60% |
Debt Instrument, Maturity Date, Description | 2024 |
Senior 4.75% Notes Due 2044 [Member] |  |
Principal amount | 1,000,000,000 |
Interest rate | 4.75% |
Debt Instrument, Maturity Date, Description | 2044 |
Senior 5.3% Notes Due 2014 [Member] |  |
Interest rate | 5.30% |
Debt Instrument, Maturity Date, Description | 2014 |
Repurchases and repayments of debt | 1,000,000,000 |
Senior 2.1% Notes Due 2014 [Member] |  |
Interest rate | 2.10% |
Debt Instrument, Maturity Date, Description | April 2014 |
Repurchases and repayments of debt | 900,000,000 |
Senior 2.1% Notes Due 2014 [Member] | NBCUniversal Media, LLC [Member] |  |
Interest rate | 2.10% |
Debt Instrument, Maturity Date, Description | April 2014 |
Repurchases and repayments of debt | 900,000,000 |
Senior 3.375% Notes Due 2025 [Member] |  |
Principal amount | 1,000,000,000 |
Interest rate | 3.375% |
Debt Instrument, Maturity Date, Description | 2025 |
Senior 4.200% Notes Due 2034 [Member] |  |
Principal amount | $ 1,000,000,000 |
Interest rate | 4.20% |
Debt Instrument, Maturity Date, Description | 2034 |

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- Definition Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Article 7 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(3)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13(2)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a(3) -Article 5 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2 -Article 9 + Details
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- Definition Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility. + References 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 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. + References No definition available. + Details
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