Date when the business acquisition agreement was executed, in CCYY-MM-DD format.

No definition available.

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- Definition

Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
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- Definition

Represents the purchase by the parent of an additional equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The purchase of the additional equity interest represented by this element increases the parent's controlling interest in the subsidiary.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Represents a sale by the parent of a portion of its equity interest in a subsidiary during the period, thereby effecting a change in total (consolidated) equity attributable to the parent. The sale of the equity interest represented by this element does not result in a loss of control by the parent.

+ References

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- Definition

Date the entity disposed of a business or a group of assets, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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- Definition

Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

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- Definition

Description of the accounting treatment for the difference between the amount at which an investment accounted for under the equity method of accounting is reported on the balance sheet and the amount of underlying equity in net assets the reporting entity has in the investee.

+ References

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Equity Method Investments (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended		3 Months Ended	6 Months Ended		12 Months Ended
	Oct. 31, 2019	Jun. 30, 2018	Jun. 30, 2019	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Dec. 31, 2018
Time Warner Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Business Acquisition, Effective Date of Acquisition		Jun. 14, 2018					Jun. 14, 2018
Time Warner Inc. [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Business Acquisition, Effective Date of Acquisition							Dec. 31, 2018
Difference between fair value and proportional book value of investments' net assets						$ 2,135
Difference between fair value and proportional book value of investments' net assets, amortization treatment						$1,397 is attributed to amortizing intangibles, which will be amortized into earnings in our “Equity net income (loss) of affiliates” over a weighted-average life of 19.4 years.
Hudson Yards North Tower Holdings LLC [Member]
Schedule of Equity Method Investments [Line Items]
Sale of interst by parent						$ 1,681	$ 0
Hudson Yards North Tower Holdings LLC [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Disposition of business - period of sale of subsidiary			Jun. 30, 2019
HBO Latin America Group [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Company's ownership interest in investee						88.20%
Date of agreement	Oct. 31, 2019
Acquisition of interests held by noncontrolling owners	$ 230
HBO Latin America Group [Member] \| Equity Method Investment [Member] \| Forecast [Member]
Schedule of Equity Method Investments [Line Items]
Business Acquisition, Effective Date of Acquisition				Dec. 31, 2020
Hulu [Member]
Schedule of Equity Method Investments [Line Items]
Sale of interst by parent						$ 689	$ 0
Hulu [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Disposition of business - period of sale of subsidiary			Jun. 30, 2019
Central European Media Enterprises Ltd. [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Company's ownership interest in investee						65.70%
Date of agreement	Oct. 31, 2019
Sale of interst by parent	$ 1,100
Central European Media Enterprises Ltd. [Member] \| Equity Method Investment [Member] \| Forecast [Member]
Schedule of Equity Method Investments [Line Items]
Disposition of business - period of sale of subsidiary					Jun. 30, 2020
SKY Mexico [Member] \| Equity Method Investment [Member]
Schedule of Equity Method Investments [Line Items]
Company's ownership interest in investee						41.30%