Programming and Production Costs (Narrative) (Details) $ in Millions	12 Months Ended
Dec. 31, 2018 USD ($)
Film And Television Cost [Line Items]
Amortization of completed film and television production expected to be amortized during the next fiscal year	$ 1,600
Expected amortization percentage of released and unamortized film and television costs during the next three fiscal years	83.00%
Remaining unamortized costs of acquired film and television libraries	$ 396
Expected amortization percentage of unamortized acquired film and television library costs during the next three fiscal years	48.00%
NBCUniversal Media LLC [Member]
Film And Television Cost [Line Items]
Amortization of completed film and television production expected to be amortized during the next fiscal year	$ 1,600
Expected amortization percentage of released and unamortized film and television costs during the next three fiscal years	83.00%
Remaining unamortized costs of acquired film and television libraries	$ 396
Expected amortization percentage of unamortized acquired film and television library costs during the next three fiscal years	48.00%
Maximum [Member]
Film And Television Cost [Line Items]
Amortization period of acquired film and television library costs	20 years
Maximum [Member] \| NBCUniversal Media LLC [Member]
Film And Television Cost [Line Items]
Amortization period of acquired film and television library costs	20 years

Acquired Film and Television Library Costs, Amortization Period

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[Line Items] for Film And Television Cost [Table]

+ References

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The remaining amount of costs related to film and television libraries that are expected to be amortized.

+ References

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- Definition

The percentage of unamortized acquired film and television library costs that are expected to be amortized within three years from the date of the balance sheet.

+ References

No definition available.

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- Definition

The amount of film costs related to completed films that are expected to be amortized during the upcoming operating cycle.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6473108&loc=d3e54406-107959

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- Definition

The percentage of unamortized film costs for released films, excluding acquired film libraries, that it expects to amortize within three years from the date of the balance sheet.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 926
-SubTopic 20
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=6473108&loc=d3e54434-107959

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