v3.5.0.2

Commitments and Contingencies (Insurance Obligations) (Details) $ in Millions	3 Months Ended
	Jun. 30, 2016 USD ($)
Expense related to the settlement of insurance obligations	$ 116

X

- Definition

Expense related to the settlement of insurance obligations recorded in other operating and administrative expenses

+ References

No definition available.

+ Details

Name:	cmcsa_ExpenseRelatedToTheSettlementOfInsuranceObligations
Namespace Prefix:	cmcsa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration