Name:	cmcsa_DistributionsToNoncontrollingInterestsAndDividendsForRedeemableSubsidiaryPreferredStock
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The cash outflow related to distributions to noncontrolling interests.

No definition available.

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The cash outflow associated with the revolving credit agreements with Comcast.

No definition available.

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The cash outflow for the acquisition and construction of buildings (properties) whether for investment or use.

No definition available.

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Represents the cash inflow from borrowings from Comcast for a note receivable issued to Comcast.

No definition available.

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The cash inflow associated with the sale of businesses and investments during the period.

No definition available.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-Glossary Cash
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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No definition available.

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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No definition available.

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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No definition available.

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The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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The cash outflow to reacquire common stock during the period.

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Cash outflow to owners or shareholders, excluding ordinary dividends. Includes special dividends.

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Cash outflow in the form of capital distributions and dividends to common shareholders, preferred shareholders and noncontrolling interests.

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The cash outflow for acquisition of buildings (properties) whether for investment or use.

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The cash outflow associated with the acquisition of a business, net of the cash acquired from the purchase.

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The cash outflow to acquire asset without physical form usually arising from contractual or other legal rights, excluding goodwill.

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Name:	us-gaap_PaymentsToAcquireIntangibleAssets
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The cash outflow associated with the purchase of all investments (debt, security, other) during the period.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Name:	us-gaap_ProceedsFromIssuanceOfLongTermDebt
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The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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Name:	us-gaap_ProceedsFromPaymentsForOtherFinancingActivities
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The net cash inflow or outflow for borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The cash outflow for the payment of other borrowing not otherwise defined in the taxonomy.

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