Restructuring and Other Corporate Matters (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended	27 Months Ended
Mar. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2019
Restructuring Reserve
Beginning balance	$ 68	$ 55
Charges	108	67	$ 63
Settlements	(27)	(54)		$ (89)
Ending balance	149	68	55	149
Other corporate matters, costs	6
Professional fees	9
Operating Segments [Member] \| Entertainment [Member]
Restructuring Reserve
Beginning balance	31	39
Charges	48	27
Settlements	(10)	(35)
Ending balance	69	31	39	69
Operating Segments [Member] \| Cable Networks [Member]
Restructuring Reserve
Beginning balance	0
Charges	5
Settlements	0
Ending balance	5	0		5
Operating Segments [Member] \| Publishing [Member]
Restructuring Reserve
Beginning balance	2	3
Charges	5	1
Settlements	0	(2)
Ending balance	7	2	3	7
Operating Segments [Member] \| Local Media [Member]
Restructuring Reserve
Beginning balance	23	11
Charges	28	18
Settlements	(5)	(6)
Ending balance	46	23	11	46
Corporate [Member]
Restructuring Reserve
Beginning balance	12	2
Charges	22	21
Settlements	(12)	(11)
Ending balance	22	12	2	22
Severance Costs [Member]
Restructuring Reserve
Charges	98	57	54
Settlements				(79)
Exiting Contractual Obligations [Member]
Restructuring Reserve
Charges	$ 10	$ 10	$ 9
Settlements				$ (10)

Other Corporate Matters, Costs

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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-Publisher FASB
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- Definition

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.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-Publisher FASB
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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
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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
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+ References

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