The cash outflow associated with a capital contribution to a VIE accounted for as an equity method investment

No definition available.

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- Definition

This element represents disclosure of the amount of gain which has been deferred as the result of a dilution in our ownership percentage in an equity method investment which deferred gain has been reflected in the accompanying statement of financial position.

+ References

No definition available.

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- Definition

Equity Method Investment, Funding Commitment

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No definition available.

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- Definition

Equity Method Investment, Funding Commitment by Management Company Investors

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- Definition

Equity Method Investment, Management Fee Funding Commitment

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No definition available.

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- Definition

Represents the percentage of any losses in an equity method investment that the Company is obligated to absorb.

+ References

No definition available.

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- Definition

Equity Method Investment, Put or Call Period

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No definition available.

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- Definition

Represents the percentage of any residual returns that Comcast has the right to receive

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No definition available.

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- Definition

Pretax gain recognized as a result of the sale of The Weather Channel's product and technology business to IBM

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No definition available.

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- Definition

Term of agreement for Atairos

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No definition available.

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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.

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- Definition

Amount of gain (loss) on sale or disposal of an equity method investment.

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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- Definition

Amount of gain (loss) from sale and disposal of integrated set of activities and assets capable of being conducted and managed for purpose of providing return in form of dividend, lower cost, or other economic benefit to investor, owner, member and participant.

+ References

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- Definition

This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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- Definition

The cash outflow associated with the purchase of or advances to an equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence.

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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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Investments (Equity Method Investments) (Details) - USD ($) $ in Millions		1 Months Ended					12 Months Ended
	Jan. 01, 2016	Apr. 30, 2018	Mar. 31, 2018	Jul. 31, 2017	Aug. 31, 2016	Jan. 31, 2016	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Feb. 28, 2018	Jul. 31, 2016
Schedule of Equity Method Investments [Line Items]
Equity method investments							$ 4,035	$ 3,546
Equity in net income (losses) of investees, net							364	(107)	$ 104
NBCUniversal Media LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments							707	690
Equity in net income (losses) of investees, net							371	201	99
Atairos [Member]
Schedule of Equity Method Investments [Line Items]
Term of agreement	12 years
Funding commitment	$ 4,000									$ 5,000
Management fee funding commitment	$ 40									45
Percent of losses	99.00%
Percentage of residual returns	86.00%
Equity method investments							2,700	2,400
Purchases of investments							282	994	1,200
Equity in net income (losses) of investees, net							(31)	281	(38)
Pretax gain, sale of business to Atairos		$ 200		$ 105
Atairos [Member] \| Maximum [Member]
Schedule of Equity Method Investments [Line Items]
Funding commitment by management company investors										100
Atairos [Member] \| Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Funding commitment by management company investors										$ 50
Atairos [Member] \| Former CFO [Member] \| Minimum [Member]
Schedule of Equity Method Investments [Line Items]
Funding commitment by management company investors	$ 40
Hulu [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments							248	249
Equity in net income (losses) of investees, net							(454)	(276)	(168)
Cash capital contributions for equity method investments							454	300	50
Ownership percentage					30.00%						33.00%
Put/call period					3 years
Deferred gain					$ 159
Hulu [Member] \| NBCUniversal Media LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments							248	249
Equity in net income (losses) of investees, net							(454)	(276)	(168)
Cash capital contributions for equity method investments							$ 454	$ 300	$ 50
Ownership percentage					30.00%						33.00%
Put/call period					3 years
Deferred gain					$ 159
Hulu [Member] \| Time Warner, Inc. [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage					10.00%
Hulu [Member] \| Time Warner, Inc. [Member] \| NBCUniversal Media LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage					10.00%
The Weather Channel [Member]
Schedule of Equity Method Investments [Line Items]
Pretax gain on sale of investment			$ 64
Pretax gain on sale of investment						$ 108
The Weather Channel [Member] \| NBCUniversal Media LLC [Member]
Schedule of Equity Method Investments [Line Items]
Pretax gain on sale of investment			$ 64
Pretax gain on sale of investment						$ 108