Amount represents the maximum borrowing capacity under the commercial paper program.

No definition available.

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- Definition

Principal amount of debt securities subject to guarantee.

+ References

No definition available.

+ Details

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- Definition

Potential increased maximum borrowing capacity under the revolving credit facility, subject to approval of the lenders.

+ References

No definition available.

+ Details

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- Definition

Represents the Company's ownership in its cable holding company subsidiaries.

+ References

No definition available.

+ Details

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- Definition

Represents the related party aggregate principal amount of senior notes not subject to guarantee by NBCUniversal.

+ References

No definition available.

+ Details

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- Definition

Represents the related party credit facility not subject to guarantee by NBCUniversal.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- 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

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
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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.

+ Details

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

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Long-Term Debt (Narrative) (Details) - USD ($)	12 Months Ended
Long-Term Debt (Narrative) (Details) - USD ($)	Dec. 31, 2016	May 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Fair value of debt	$ 66,300,000,000		$ 58,000,000,000
Amounts available under revolving credit facilities	5,500,000,000
Unused irrevocable standby letters of credit	$ 443,000,000
NBCUniversal Enterprise Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		$ 1,500,000,000.0
Potential increase of maximum borrowing capacity		2,000,000,000
Borrowing margin for LIBOR based borrowings	1.00%
Amounts available under revolving credit facilities	$ 460,000,000
Former Comcast And Comcast Cable Communications, LLC Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		6,250,000,000.00
Former NBCUniversal Enterprise Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		1,350,000,000.00
Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper capacity	6,250,000,000.00
NBCUniversal Enterprise Commercial Paper [Member]
Debt Instrument [Line Items]
Commercial paper capacity	1,350,000,000.00
Comcast Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity		7,000,000,000
Potential increase of maximum borrowing capacity		$ 10,000,000,000
NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Fair value of debt	$ 12,600,000,000		$ 13,400,000,000
Ownership in cable holding company subsidiaries	100.00%
NBCUniversal Media LLC [Member] \| Comcast And Comcast Cable Debt Securities [Member]
Debt Instrument [Line Items]
Principal amount of debt securities subject to guarantee	$ 44,700,000,000
NBCUniversal Media LLC [Member] \| Comcast Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Principal amount of debt securities subject to guarantee	7,000,000,000
NBCUniversal Enterprise [Member] \| NBCUniversal Media LLC [Member]
Debt Instrument [Line Items]
Related party aggregate principal amount senior notes not subject to guarantee	3,300,000,000
Related party credit facility not subject to guarantee	1,500,000,000.0
Related party liquidation preference preferred stock not subject to guarantee	$ 725,000,000