Financial Data by Business Segment (Details) $ in Millions	3 Months Ended		6 Months Ended
Financial Data by Business Segment (Details) $ in Millions	Jun. 30, 2017 USD ($)	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) segment	Jun. 30, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			5
Financial Data by Business Segment
Revenue	$ 21,165	$ 19,269	$ 41,628	$ 38,059
Adjusted EBITDA	7,099	6,455	14,131	12,822
Depreciation and Amortization	2,541	2,389	5,043	4,667
Operating Income (Loss)	4,558	4,066	9,088	8,155
Capital Expenditures	2,327	2,271	4,405	4,156
Cash Paid for Intangible Assets	420	359	$ 836	737
Disclosure of major customers			No single customer accounted for a significant amount of revenue in any period.
NBCUniversal Media LLC [Member]
Segment Reporting Information [Line Items]
Number of reportable segments \| segment			4
Financial Data by Business Segment
Revenue	8,331	7,103	$ 16,199	13,964
Adjusted EBITDA	2,071	1,689	4,088	3,311
Depreciation and Amortization	520	465	1,028	879
Operating Income (Loss)	1,551	1,224	3,060	2,432
Capital Expenditures	338	360	623	655
Cash Paid for Intangible Assets	73	62	$ 128	114
Disclosure of major customers			No single customer accounted for a significant amount of revenue in any period.
NBCUniversal Segments [Member]
Financial Data by Business Segment
Revenue	8,331	7,103	$ 16,199	13,964
Adjusted EBITDA	2,071	1,689	4,088	3,311
Depreciation and Amortization	520	465	1,028	879
Operating Income (Loss)	1,551	1,224	3,060	2,432
Capital Expenditures	338	360	623	655
Cash Paid for Intangible Assets	73	62	128	114
Operating Segments [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Revenue	13,122	12,444	26,034	24,648
Adjusted EBITDA	5,320	5,048	10,518	9,937
Depreciation and Amortization	2,001	1,904	3,981	3,747
Operating Income (Loss)	3,319	3,144	6,537	6,190
Capital Expenditures	1,956	1,881	3,737	3,457
Cash Paid for Intangible Assets	$ 327	$ 289	$ 679	$ 613
Cable segment revenue types as percentage of total cable revenue	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] \| Cable Networks [Member]
Financial Data by Business Segment
Revenue	$ 2,696	$ 2,566	$ 5,337	$ 5,019
Adjusted EBITDA	1,055	944	2,171	1,900
Depreciation and Amortization	181	187	395	377
Operating Income (Loss)	874	757	1,776	1,523
Capital Expenditures	8	7	10	8
Cash Paid for Intangible Assets	4	3	7	4
Operating Segments [Member] \| Cable Networks [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	2,696	2,566	5,337	5,019
Adjusted EBITDA	1,055	944	2,171	1,900
Depreciation and Amortization	181	187	395	377
Operating Income (Loss)	874	757	1,776	1,523
Capital Expenditures	8	7	10	8
Cash Paid for Intangible Assets	4	3	7	4
Operating Segments [Member] \| Broadcast Television [Member]
Financial Data by Business Segment
Revenue	2,241	2,128	4,449	4,212
Adjusted EBITDA	416	394	738	678
Depreciation and Amortization	31	30	63	62
Operating Income (Loss)	385	364	675	616
Capital Expenditures	30	30	59	49
Cash Paid for Intangible Assets	4	3	7	6
Operating Segments [Member] \| Broadcast Television [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	2,241	2,128	4,449	4,212
Adjusted EBITDA	416	394	738	678
Depreciation and Amortization	31	30	63	62
Operating Income (Loss)	385	364	675	616
Capital Expenditures	30	30	59	49
Cash Paid for Intangible Assets	4	3	7	6
Operating Segments [Member] \| Filmed Entertainment [Member]
Financial Data by Business Segment
Revenue	2,155	1,351	4,136	2,734
Adjusted EBITDA	285	56	653	223
Depreciation and Amortization	26	12	47	20
Operating Income (Loss)	259	44	606	203
Capital Expenditures	19	5	29	8
Cash Paid for Intangible Assets	6	3	11	6
Operating Segments [Member] \| Filmed Entertainment [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	2,155	1,351	4,136	2,734
Adjusted EBITDA	285	56	653	223
Depreciation and Amortization	26	12	47	20
Operating Income (Loss)	259	44	606	203
Capital Expenditures	19	5	29	8
Cash Paid for Intangible Assets	6	3	11	6
Operating Segments [Member] \| Theme Parks [Member]
Financial Data by Business Segment
Revenue	1,314	1,136	2,432	2,162
Adjusted EBITDA	551	469	948	844
Depreciation and Amortization	186	145	328	243
Operating Income (Loss)	365	324	620	601
Capital Expenditures	243	240	472	440
Cash Paid for Intangible Assets	26	20	39	29
Operating Segments [Member] \| Theme Parks [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	1,314	1,136	2,432	2,162
Adjusted EBITDA	551	469	948	844
Depreciation and Amortization	186	145	328	243
Operating Income (Loss)	365	324	620	601
Capital Expenditures	243	240	472	440
Cash Paid for Intangible Assets	26	20	39	29
Corporate, Non-Segment [Member]
Financial Data by Business Segment
Revenue	205	180	413	379
Adjusted EBITDA	(302)	(291)	(496)	(445)
Depreciation and Amortization	20	20	34	41
Operating Income (Loss)	(322)	(311)	(530)	(486)
Capital Expenditures	33	30	45	44
Cash Paid for Intangible Assets	20	8	29	10
Corporate, Non-Segment [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	9	6	17	9
Adjusted EBITDA	(235)	(175)	(420)	(335)
Depreciation and Amortization	96	91	195	177
Operating Income (Loss)	(331)	(266)	(615)	(512)
Capital Expenditures	38	78	53	150
Cash Paid for Intangible Assets	33	33	64	69
Corporate, Non-Segment [Member] \| NBCUniversal Segments [Member]
Financial Data by Business Segment
Revenue	9	6	17	9
Adjusted EBITDA	(235)	(175)	(420)	(335)
Depreciation and Amortization	96	91	195	177
Operating Income (Loss)	(331)	(266)	(615)	(512)
Capital Expenditures	38	78	53	150
Cash Paid for Intangible Assets	33	33	64	69
Eliminations [Member]
Financial Data by Business Segment
Revenue	(493)	(458)	(1,018)	(932)
Adjusted EBITDA	10	9	21	19
Depreciation and Amortization	0	0	0	0
Operating Income (Loss)	10	9	21	19
Capital Expenditures	0	0	0	0
Cash Paid for Intangible Assets	0	0	0	0
Eliminations [Member] \| NBCUniversal Media LLC [Member]
Financial Data by Business Segment
Revenue	(84)	(84)	(172)	(172)
Adjusted EBITDA	(1)	1	(2)	1
Depreciation and Amortization	0	0	0	0
Operating Income (Loss)	(1)	1	(2)	1
Capital Expenditures	0	0	0	0
Cash Paid for Intangible Assets	0	0	0	0
Eliminations [Member] \| NBCUniversal Segments [Member]
Financial Data by Business Segment
Revenue	(84)	(84)	(172)	(172)
Adjusted EBITDA	(1)	1	(2)	1
Depreciation and Amortization	0	0	0	0
Operating Income (Loss)	(1)	1	(2)	1
Capital Expenditures	0	0	0	0
Cash Paid for Intangible Assets	$ 0	$ 0	$ 0	$ 0
Residential Video Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	44.20%	44.90%	44.40%	45.10%
Residential High-speed Internet Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	28.00%	27.10%	28.00%	27.00%
Residential Voice Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	6.50%	7.20%	6.60%	7.30%
Business Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	11.70%	10.90%	11.60%	10.80%
Advertising Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	4.40%	4.70%	4.20%	4.60%
Other Products And Services [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	5.20%	5.20%	5.20%	5.20%
Franchise And Other Regulatory Fees [Member] \| Operating Segments [Member] \| Cable Communications [Member]
Financial Data by Business Segment
Cable segment revenue types as percentage of total cable revenue	2.80%	2.80%	2.80%	2.80%

NBCUniversal Media, LLC 10-Q