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Other operating and administrative expense recognized in the period not presented separately.

No definition available.

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Programming and Production Costs

No definition available.

Name:	cmcsa_ProgrammingAndProductionCosts
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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

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-Glossary Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=16317811

Reference 3: http://www.xbrl.org/2003/role/presentationRef

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-Glossary Net Income

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Total costs of sales and operating expenses for the period.

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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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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.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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-Name Accounting Standards Codification

-Topic 235

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-Number 210

-Section 08

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-Name Accounting Standards Codification

-Glossary Income Tax Expense (or Benefit)

-URI http://asc.fasb.org/extlink&oid=6515339

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-Topic 740

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Amount of the cost of borrowed funds accounted for as interest expense.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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-Name Accounting Standards Codification

-Topic 942

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-Paragraph 1

-Subparagraph (SX 210.9-04.9)

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-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

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The aggregate amount of income from investments (for example, dividends) not considered a component of the entity's core operations.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

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-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.7)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Number 210

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Revenue, comprised of base and incentive revenue derived from the management of joint ventures, managing third-party properties, or another entity's operations.

Name:	us-gaap_ManagementFeesRevenue
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The total expense recognized in the period for promotion, public relations, and brand or product advertising.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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-Name Regulation S-X (SX)

-Number 210

-Section 04

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-Topic 230

-SubTopic 10

-Section 45

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-Name Accounting Standards Codification

-Glossary Other Comprehensive Income

-URI http://asc.fasb.org/extlink&oid=6519514

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Net Income

-URI http://asc.fasb.org/extlink&oid=6518256

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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-Topic 944

-SubTopic 225

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-Paragraph 1

-Subparagraph (SX 210.7-04.19)

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-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.18)

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-URI http://asc.fasb.org/extlink&oid=28358780&loc=d3e565-108580

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 19

-Article 5

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The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

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The net result for the period of deducting operating expenses from operating revenues.

No definition available.

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The net amount of other income and expense amounts, the components of which are not separately disclosed on the income statement, resulting from ancillary business-related activities (that is, excluding major activities considered part of the normal operations of the business) also known as other nonoperating income (expense) recognized for the period. Such amounts may include: (a) dividends, (b) interest on securities, (c) net gains or losses on securities, (d) unusual costs, (e) gains or losses on foreign exchange transactions, and (f) miscellaneous other income and expense items.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Subparagraph (SX 210.5-03.9)

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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-Topic 810

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-Topic 810

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-Section 45

-Paragraph 19

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4569616-111683

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-Subparagraph (a),(c)

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-URI http://asc.fasb.org/extlink&oid=31814832&loc=SL4591551-111686

Name:	us-gaap_ProfitLoss
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

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Aggregate revenue during the period from services rendered in the normal course of business, after deducting allowances and discounts.

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-Paragraph 2

-Subparagraph (SX 210.5-03.1(d))

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-Number 210

-Section 03

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