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Significant Transactions (Sky Offer) (Details) £ / shares in Units, £ in Billions, $ in Billions	Jul. 11, 2018 USD ($)	Jul. 11, 2018 GBP (£) £ / shares	Jun. 30, 2018 USD ($)	Apr. 25, 2018 USD ($)	Apr. 25, 2018 GBP (£)
Revolving Credit Facility [Member]
Business Acquisition [Line Items]
Amount available under existing credit facility | $			$ 7
Sky PLC [Member]
Business Acquisition [Line Items]
Unsecured bridge credit agreement maximum borrowing capacity				$ 22	£ 16
Unsecured term loan credit agreement maximum borrowing capacity				$ 10	£ 7
Sky PLC [Member] | Subsequent Event [Member]
Business Acquisition [Line Items]
Cash offer price per share (in gbp per share) | £ / shares		£ 14.75
Offer consideration	$ 34	£ 26
Acquisition conditions, percentage of secured acceptance of voting rights		50.00%

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- Definition

The conditions of the business acquisition include securing acceptances of voting rights that must be more than the stated percentage.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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