Carrying value of future obligation classified as a liability which is no longer recorded at fair value.

No definition available.

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- Definition

[Line Items] for Commitment And Contingencies [Table]

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
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- Definition

Contractual value of a potential future obligation based on a contractual formula on a specified date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Gain related to the settlement of a contingent consideration obligation recorded in other income (expense), net.

+ References

No definition available.

+ Details

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- Definition

Number of employees covered by collective bargaining agreements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Shares of preferred stock can be called for redemption by NBCUniversal Enterprise at a price equal to the liquidation preference plus accrued but unpaid dividends one year following the put date applicable to such shares.

+ References

No definition available.

+ Details

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- Definition

The holders have the right to cause NBCUniversal Enterprise to redeem their shares at a price equal to the liquidation preference plus accrued but unpaid dividends for a 30 day period beginning on March 19, 2020 and thereafter on every third anniversary of such date (each such date, a “put date”).

+ References

No definition available.

+ Details

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Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Represents the related party liquidation preference of preferred stock not subject to guarantee by NBCUniversal.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Definition

Temporary Equity, Fair Value of our redeemable subsidiary preferred stock.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=84177426&loc=d3e6351-108592

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+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Amount of cash outflow, not made soon after acquisition date of business combination, to settle contingent consideration liability up to amount recognized at acquisition date, including, but not limited to, measurement period adjustment and less amount paid soon after acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (f)
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The percentage rate used to calculate dividend payments on preferred stock.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

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- Details

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Commitments and Contingencies (Narrative) (Details) $ in Millions	1 Months Ended	12 Months Ended
	Jun. 30, 2015 USD ($)	Dec. 31, 2017 USD ($) employee	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Commitment And Contingencies [Line Items]
Carrying value of contractual obligation		$ 1,100
Contractual value of a potential obligation		1,500
Payment for contingent consideration	$ 450
Gain on settlement of contingent consideration	$ 240
Charge related to legal settlement		250	$ 0	$ 0
Sprint Communications Company L.P. Lawsuit [Member] \| Settled Litigation [Member]
Commitment And Contingencies [Line Items]
Charge related to legal settlement		250
NBCUniversal Enterprise [Member]
Commitment And Contingencies [Line Items]
Related party liquidation preference preferred stock not subject to guarantee		$ 725
NBCUniversal Enterprise [Member] \| Redeemable Subsidiary Preferred Stock [Member]
Commitment And Contingencies [Line Items]
Redeemable subsidiary preferred stock, put period		30 days
Redeemable subsidiary preferred stock, dividend rate		5.25%
Redeemable subsidiary preferred stock, call period		1 year
NBCUniversal Enterprise [Member] \| Redeemable Subsidiary Preferred Stock [Member] \| Level 2 [Member]
Commitment And Contingencies [Line Items]
Temporary equity, fair value of redeemable subsidiary preferred stock		$ 748	$ 741
NBCUniversal Media LLC [Member]
Commitment And Contingencies [Line Items]
Carrying value of contractual obligation		1,100
Contractual value of a potential obligation		1,500
NBCUniversal Media LLC [Member] \| NBCUniversal Enterprise [Member]
Commitment And Contingencies [Line Items]
Related party liquidation preference preferred stock not subject to guarantee		$ 725
Workforce Subject to Collective Bargaining Arrangements [Member]
Commitment And Contingencies [Line Items]
Number of employees covered under collective bargaining agreements \| employee		9,500
Workforce Subject to Collective Bargaining Arrangements [Member] \| NBCUniversal Media LLC [Member]
Commitment And Contingencies [Line Items]
Number of employees covered under collective bargaining agreements \| employee		9,500
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member]
Commitment And Contingencies [Line Items]
Percentage of full-time equivalent employees covered by collective bargaining agreements that have expired or are schedule to expire during the next year		63.00%
Workforce Subject to Collective Bargaining Arrangements Expiring within One Year [Member] \| NBCUniversal Media LLC [Member]
Commitment And Contingencies [Line Items]
Percentage of full-time equivalent employees covered by collective bargaining agreements that have expired or are schedule to expire during the next year		63.00%