v2.4.0.6
Condensed Consolidating Financial Information (Condensed Consolidating Balance Sheet) (Details) (USD $)
In Millions, unless otherwise specified
Mar. 31, 2013
Dec. 31, 2012
Mar. 31, 2012
Dec. 31, 2011
Cash and cash equivalents $ 1,839 $ 10,951 $ 2,207 $ 1,620
Investments [Current] 2,841 1,464    
Receivables, net 5,063 5,521    
Programming rights 901 909    
Other current assets 1,139 1,146    
Total current assets 11,783 19,991    
Film and television costs 4,653 5,054    
Investments 5,433 6,325    
Investments in and amounts due from subsidiaries eliminated upon consolidation 0      
Property and equipment, net 28,219 27,232    
Franchise rights 59,364 59,364    
Goodwill 26,996 26,985    
Other intangible assets, net 17,584 17,840    
Other noncurrent assets, net 2,332 2,180    
Total assets 156,364 164,971    
Accounts payable and accrued expenses related to trade creditors 5,750 6,206    
Accrued participations and residuals 1,469 1,350    
Accrued expenses and other current liabilities [condensed] 8,622 6,782    
Current portion of long-term debt 2,177 2,376    
Total current liabilities 18,018 16,714    
Long-term debt, less current portion 45,049 38,082    
Deferred income taxes 31,152 30,110    
Other noncurrent liabilities 12,640 13,271    
Redeemable Noncontrolling Interests And Redeemable Subsidiary Preferred Stock 854 16,998    
Common stock 31 31    
Other shareholders' equity 48,159 49,325    
Total Comcast Corporation shareholders' equity 48,190 49,356    
Noncontrolling interests 461 440    
Total equity 48,651 49,796 47,821 47,655
Total liabilities and equity 156,364 164,971    
Comcast [Member]
        
Other current assets 224 233    
Total current assets 224 233    
Investments 8      
Investments in and amounts due from subsidiaries eliminated upon consolidation 76,651 74,227    
Property and equipment, net 235 242    
Other intangible assets, net 11 12    
Other noncurrent assets, net 1,045 1,130    
Total assets 78,174 75,844    
Accounts payable and accrued expenses related to trade creditors 8 8    
Accrued expenses and other current liabilities [condensed] 1,355 1,290    
Current portion of long-term debt 1,530 0    
Total current liabilities 2,893 1,298    
Long-term debt, less current portion 25,122 23,306    
Other noncurrent liabilities 1,969 1,884    
Common stock 31 31    
Other shareholders' equity 48,159 49,325    
Total Comcast Corporation shareholders' equity 48,190 49,356    
Total equity 48,190 49,356    
Total liabilities and equity 78,174 75,844    
Comcast Holdings [Member]
        
Investments in and amounts due from subsidiaries eliminated upon consolidation 90,959 87,630    
Other noncurrent assets, net 146 147    
Total assets 91,105 87,777    
Accrued expenses and other current liabilities [condensed] 277 275    
Current portion of long-term debt 0 0    
Total current liabilities 277 275    
Long-term debt, less current portion 117 113    
Deferred income taxes 760 754    
Other shareholders' equity 89,951 86,635    
Total Comcast Corporation shareholders' equity 89,951 86,635    
Total equity 89,951 86,635    
Total liabilities and equity 91,105 87,777    
CCCL Parent [Member]
        
Other current assets 4 14    
Total current assets 4 14    
Investments in and amounts due from subsidiaries eliminated upon consolidation 96,939 96,853    
Other noncurrent assets, net   1    
Total assets 96,943 96,868    
Accrued expenses and other current liabilities [condensed] 303 210    
Current portion of long-term debt 384 2,105    
Total current liabilities 687 2,315    
Long-term debt, less current portion 1,827 1,827    
Other shareholders' equity 94,429 92,726    
Total Comcast Corporation shareholders' equity 94,429 92,726    
Total equity 94,429 92,726    
Total liabilities and equity 96,943 96,868    
Combined CCHMO Parents [Member]
        
Other current assets 2 4    
Total current assets 2 4    
Investments in and amounts due from subsidiaries eliminated upon consolidation 50,775 50,242    
Total assets 50,777 50,246    
Accrued expenses and other current liabilities [condensed] 24 54    
Current portion of long-term debt 240 241    
Total current liabilities 264 295    
Long-term debt, less current portion 1,510 1,512    
Other shareholders' equity 49,003 48,439    
Total Comcast Corporation shareholders' equity 49,003 48,439    
Total equity 49,003 48,439    
Total liabilities and equity 50,777 50,246    
NBCUniversal Media Parent [Member]
        
Cash and cash equivalents 313 5,129 264 238
Receivables, net   3    
Other current assets 47 51    
Total current assets 360 5,183    
Investments 527 529    
Investments in and amounts due from subsidiaries eliminated upon consolidation 40,360 38,464    
Other noncurrent assets, net 116 152    
Total assets 41,363 44,328    
Accrued expenses and other current liabilities [condensed] 346 263    
Current portion of long-term debt 2 7    
Total current liabilities 348 270    
Long-term debt, less current portion 11,134 11,219    
Deferred income taxes 121 78    
Other noncurrent liabilities 957 926    
Other shareholders' equity 28,803 31,835    
Total Comcast Corporation shareholders' equity 28,803 31,835    
Total equity 28,803 31,835    
Total liabilities and equity 41,363 44,328    
Comcast Non-Guarantor Subsidiaries [Member]
        
Cash and cash equivalents 1,526 5,822 1,943 1,382
Investments [Current] 2,841 1,464    
Receivables, net 5,063 5,518    
Programming rights 901 909    
Other current assets 862 844    
Total current assets 11,193 14,557    
Film and television costs 4,653 5,054    
Investments 4,898 5,796    
Investments in and amounts due from subsidiaries eliminated upon consolidation 77,765 73,298    
Property and equipment, net 27,984 26,990    
Franchise rights 59,364 59,364    
Goodwill 26,996 26,985    
Other intangible assets, net 17,573 17,828    
Other noncurrent assets, net 1,898 1,650    
Total assets 232,324 231,522    
Accounts payable and accrued expenses related to trade creditors 5,742 6,198    
Accrued participations and residuals 1,469 1,350    
Accrued expenses and other current liabilities [condensed] 6,317 4,690    
Current portion of long-term debt 21 23    
Total current liabilities 13,549 12,261    
Long-term debt, less current portion 5,339 105    
Deferred income taxes 31,001 30,035    
Other noncurrent liabilities 9,857 10,604    
Redeemable Noncontrolling Interests And Redeemable Subsidiary Preferred Stock 854 16,998    
Other shareholders' equity 171,263 161,079    
Total Comcast Corporation shareholders' equity 171,263 161,079    
Noncontrolling interests 461 440    
Total equity 171,724 161,519    
Total liabilities and equity 232,324 231,522    
Elimination and Consolidation Adjustments [Member]
        
Investments in and amounts due from subsidiaries eliminated upon consolidation (433,449) (420,714)    
Other noncurrent assets, net (873) (900)    
Total assets (434,322) (421,614)    
Deferred income taxes (730) (757)    
Other noncurrent liabilities (143) (143)    
Other shareholders' equity (433,449) (420,714)    
Total Comcast Corporation shareholders' equity (433,449) (420,714)    
Total equity (433,449) (420,714)    
Total liabilities and equity $ (434,322) $ (421,614)