Derivative Instruments (Basis Swaps, Interest Rate Caps and Collars) (Details) $ in Millions	9 Months Ended
Sep. 30, 2020 USD ($) derivative_instrument
Interest Rate Collar
Derivative [Line Items]
Number of derivative instruments \| derivative_instrument	0
Interest Rate Caps
Derivative [Line Items]
Notional amount of derivative	$ 468.9
Interest Rate Floor
Derivative [Line Items]
Notional amount of derivative	$ 4,838.9
UPC Holding \| Basis Swaps
Derivative [Line Items]
Weighted average remaining life	9 days
Telenet \| Basis Swaps
Derivative [Line Items]
Weighted average remaining life	9 days
Other \| Basis Swaps
Derivative [Line Items]
Weighted average remaining life	9 days
Due from Counterparty \| UPC Holding \| Basis Swaps
Derivative [Line Items]
Notional amount of derivative	$ 700.0
Due from Counterparty \| Telenet \| Basis Swaps
Derivative [Line Items]
Notional amount of derivative	2,295.0
Due from Counterparty \| Other \| Basis Swaps
Derivative [Line Items]
Notional amount of derivative	$ 98.8

Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

The number of derivative instruments of a particular group held by the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
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-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

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