v3.4.0.3
Condensed Consolidating Financial Information (Condensed Consolidating Statement of Income) (Details) - USD ($)
$ in Millions
 3 Months Ended
Mar. 31, 2016
Mar. 31, 2015
Service revenue $ 18,790 $ 17,853
Management fee revenue 0 0
Revenue 18,790 17,853
Costs and Expenses:    
Programming and production 5,431 5,463
Other operating and administrative 5,525 5,074
Advertising, marketing and promotion 1,467 1,360
Depreciation 1,785 1,634
Amortization 493 432
Costs and expenses, total 14,701 13,963
Operating income (loss) 4,089 3,890
Other Income (Expense):    
Interest expense (703) (656)
Investment income (loss), net 30 33
Equity in net income (losses) of investees, net (11) 33
Other income (expense), net 130 102
Nonoperating income (Expense), Total (554) (488)
Income (loss) before income taxes 3,535 3,402
Income tax (expense) benefit (1,311) (1,261)
Net income (loss) 2,224 2,141
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock (90) (82)
Net income (loss) attributable to Parent 2,134 2,059
Comprehensive income attributable to Parent 2,224 2,017
Elimination and Consolidation Adjustments [Member]    
Service revenue 0 0
Management fee revenue (513) (481)
Revenue (513) (481)
Costs and Expenses:    
Programming and production 0 0
Other operating and administrative (513) (481)
Advertising, marketing and promotion 0 0
Depreciation 0 0
Amortization 0 0
Costs and expenses, total (513) (481)
Operating income (loss) 0 0
Other Income (Expense):    
Interest expense 0 0
Investment income (loss), net 0 0
Equity in net income (losses) of investees, net (9,043) (8,623)
Other income (expense), net 0 0
Nonoperating income (Expense), Total (9,043) (8,623)
Income (loss) before income taxes (9,043) (8,623)
Income tax (expense) benefit 0 0
Net income (loss) (9,043) (8,623)
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock 0 0
Net income (loss) attributable to Parent (9,043) (8,623)
Comprehensive income attributable to Parent (9,235) (8,553)
Comcast Parent [Member]    
Service revenue 0 0
Management fee revenue 259 244
Revenue 259 244
Costs and Expenses:    
Programming and production 0 0
Other operating and administrative 156 226
Advertising, marketing and promotion 0 0
Depreciation 8 8
Amortization 1 1
Costs and expenses, total 165 235
Operating income (loss) 94 9
Other Income (Expense):    
Interest expense (451) (410)
Investment income (loss), net 0 1
Equity in net income (losses) of investees, net 2,366 2,322
Other income (expense), net 0 (5)
Nonoperating income (Expense), Total 1,915 1,908
Income (loss) before income taxes 2,009 1,917
Income tax (expense) benefit 125 142
Net income (loss) 2,134 2,059
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock 0 0
Net income (loss) attributable to Parent 2,134 2,059
Comprehensive income attributable to Parent 2,224 2,017
Comcast Holdings [Member]    
Service revenue 0 0
Management fee revenue 0 0
Revenue 0 0
Costs and Expenses:    
Programming and production 0 0
Other operating and administrative 0 0
Advertising, marketing and promotion 0 0
Depreciation 0 0
Amortization 0 0
Costs and expenses, total 0 0
Operating income (loss) 0 0
Other Income (Expense):    
Interest expense (3) (3)
Investment income (loss), net 0 2
Equity in net income (losses) of investees, net 2,264 2,226
Other income (expense), net 0 0
Nonoperating income (Expense), Total 2,261 2,225
Income (loss) before income taxes 2,261 2,225
Income tax (expense) benefit 1 0
Net income (loss) 2,262 2,225
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock 0 0
Net income (loss) attributable to Parent 2,262 2,225
Comprehensive income attributable to Parent 2,306 2,209
CCCL Parent [Member]    
Service revenue 0 0
Management fee revenue 254 237
Revenue 254 237
Costs and Expenses:    
Programming and production 0 0
Other operating and administrative 254 237
Advertising, marketing and promotion 0 0
Depreciation 0 0
Amortization 0 0
Costs and expenses, total 254 237
Operating income (loss) 0 0
Other Income (Expense):    
Interest expense (59) (73)
Investment income (loss), net 0 0
Equity in net income (losses) of investees, net 2,114 1,992
Other income (expense), net 0 0
Nonoperating income (Expense), Total 2,055 1,919
Income (loss) before income taxes 2,055 1,919
Income tax (expense) benefit 21 25
Net income (loss) 2,076 1,944
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock 0 0
Net income (loss) attributable to Parent 2,076 1,944
Comprehensive income attributable to Parent 2,078 1,942
NBCUniversal Media Parent [Member]    
Service revenue 0 0
Management fee revenue 0 0
Revenue 0 0
Costs and Expenses:    
Programming and production 0 0
Other operating and administrative 295 237
Advertising, marketing and promotion 0 0
Depreciation 0 0
Amortization 0 0
Costs and expenses, total 295 237
Operating income (loss) (295) (237)
Other Income (Expense):    
Interest expense (117) (120)
Investment income (loss), net (2) (6)
Equity in net income (losses) of investees, net 1,297 1,231
Other income (expense), net 124 (11)
Nonoperating income (Expense), Total 1,302 1,094
Income (loss) before income taxes 1,007 857
Income tax (expense) benefit (5) (5)
Net income (loss) 1,002 852
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock 0 0
Net income (loss) attributable to Parent 1,002 852
Comprehensive income attributable to Parent 1,146 801
Comcast Non-Guarantor Subsidiaries [Member]    
Service revenue 18,790 17,853
Management fee revenue 0 0
Revenue 18,790 17,853
Costs and Expenses:    
Programming and production 5,431 5,463
Other operating and administrative 5,333 4,855
Advertising, marketing and promotion 1,467 1,360
Depreciation 1,777 1,626
Amortization 492 431
Costs and expenses, total 14,500 13,735
Operating income (loss) 4,290 4,118
Other Income (Expense):    
Interest expense (73) (50)
Investment income (loss), net 32 36
Equity in net income (losses) of investees, net 991 885
Other income (expense), net 6 118
Nonoperating income (Expense), Total 956 989
Income (loss) before income taxes 5,246 5,107
Income tax (expense) benefit (1,453) (1,423)
Net income (loss) 3,793 3,684
Net (income) loss attributable to noncontrolling interests and redeemable subsidiary preferred stock (90) (82)
Net income (loss) attributable to Parent 3,703 3,602
Comprehensive income attributable to Parent $ 3,705 $ 3,601