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Restructuring, Impairment, and Other Corporate Matters (Rollforward) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			$ 400
Charges	$ 134	$ 0	336	$ 128
Payments			(213)
Other			(14)
Restructuring reserve, ending balance	463		463
Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			290
Stock-Based Compensation Expense [Member]
Restructuring Reserve [Roll Forward]
Charges			46
Operating Segments [Member] \| TV Entertainment [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			99
Payments			(41)
Other			0
Restructuring reserve, ending balance	133		133
Operating Segments [Member] \| TV Entertainment [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			75
Operating Segments [Member] \| Cable Networks [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			137
Payments			(85)
Other			(6)
Restructuring reserve, ending balance	181		181
Operating Segments [Member] \| Cable Networks [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			135
Operating Segments [Member] \| Filmed Entertainment [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			17
Payments			(5)
Other			2
Restructuring reserve, ending balance	25		25
Operating Segments [Member] \| Filmed Entertainment [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			11
Operating Segments [Member] \| Publishing [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			4
Payments			(2)
Other			(1)
Restructuring reserve, ending balance	3		3
Operating Segments [Member] \| Publishing [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			2
Corporate [Member]
Restructuring Reserve [Roll Forward]
Restructuring reserve, beginning balance			143
Payments			(80)
Other			(9)
Restructuring reserve, ending balance	$ 121		121
Corporate [Member] \| Restructuring Charges Excluding Stock-Based Compensation [Member]
Restructuring Reserve [Roll Forward]
Charges			$ 67