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This item represents the entity's proportionate share for the period of a goodwill impairment charge recorded by its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. The amount is recorded in equity in net income (losses) of investees, net.

No definition available.

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Amount represents annual commitment to Atairos Group for management fee

No definition available.

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Amount represents commitment to Atairos

No definition available.

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

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Term of agreement for Atairos

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Represents the percentage of any losses in Atairos Group, Inc. that Comcast is obligated to absorb

No definition available.

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Represents the percentage of any residual returns in Atairos Group, Inc. that Comcast has the right to receive

No definition available.

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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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35755396&loc=d3e33749-111570

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.12)
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 9
-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 11
-Article 7

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Name:	cmcsa_LegalEntity1Axis=cmcsa_AtairosMember
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