Condensed Consolidated Financial Statements (Details) - Sky Limited [Member] $ in Millions, £ in Billions	Oct. 09, 2018 USD ($)	Oct. 09, 2018 GBP (£)
Business Acquisition [Line Items]
Interest in business acquired in acquisition	100.00%	100.00%
Cash consideration transferred by Comcast	$ 39,387	£ 30.2

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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