v2.4.0.8

Supplemental Financial Information (Other Cash Flow Information) (Details) (USD $) In Millions, unless otherwise specified | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2013 NBCUniversal Media, LLC [Member] | Dec. 31, 2012 NBCUniversal Media, LLC [Member] | Jan. 28, 2011 NBCUniversal Media, LLC [Member] | Dec. 31, 2013 Successor [Member] NBCUniversal Media, LLC [Member] | Dec. 31, 2012 Successor [Member] NBCUniversal Media, LLC [Member] | Dec. 31, 2011 Successor [Member] NBCUniversal Media, LLC [Member] | Jan. 28, 2011 Successor [Member] NBCUniversal Media, LLC [Member] | Jan. 28, 2011 Predecessor [Member] NBCUniversal Media, LLC [Member] | Dec. 31, 2010 Predecessor [Member] NBCUniversal Media, LLC [Member]
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Cash and cash equivalents, beginning of year | $ 1,718 | $ 10,951 | $ 1,620 | $ 5,984 | $ 967 | $ 5,921 |  | $ 967 | $ 5,921 | $ 808 | $ 508 | $ 470 | $ 1,084
Comcast Content Business Contributed Cash Balances |  |  |  |  |  |  | 38 |  |  |  |  |  |
Cash and cash equivalents, end of year | $ 1,718 | $ 10,951 | $ 1,620 | $ 5,984 | $ 967 | $ 5,921 |  | $ 967 | $ 5,921 | $ 808 | $ 508 | $ 470 | $ 1,084

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- Definition Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash -URI http://asc.fasb.org/extlink&oid=6506951 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Cash Equivalents -URI http://asc.fasb.org/extlink&oid=6507016 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 1 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.1) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=28358313&loc=d3e6676-107765 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3044-108585 + Details
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