Restructuring Charges and Other Corporate Matters (Rollforward) (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	$ 400
Charges	202	$ 128
Payments	(99)
Other	(4)
Restructuring reserve, ending balance	465
Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	168
Stock-Based Compensation Expense [Member]
Restructuring Reserve [Roll Forward]
Charges	34
Operating Segments [Member] \| TV Entertainment [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	99
Payments	(21)
Other	(1)
Restructuring reserve, ending balance	105
Operating Segments [Member] \| TV Entertainment [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	28
Operating Segments [Member] \| Cable Networks [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	137
Payments	(16)
Other	(1)
Restructuring reserve, ending balance	216
Operating Segments [Member] \| Cable Networks [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	96
Operating Segments [Member] \| Filmed Entertainment [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	17
Payments	(3)
Other	1
Restructuring reserve, ending balance	16
Operating Segments [Member] \| Filmed Entertainment [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	1
Operating Segments [Member] \| Publishing [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	4
Payments	(1)
Other	0
Restructuring reserve, ending balance	4
Operating Segments [Member] \| Publishing [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	1
Corporate [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance	143
Payments	(58)
Other	(3)
Restructuring reserve, ending balance	124
Corporate [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges	$ 42

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 17
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3367-108585

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140864-122747

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.P.4(b))
-URI http://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Restructuring Reserve, Other Adjustment

+ References

No definition available.

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