Shareholder Inventive Program, Percent of Annual Incentive Compensation

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- Definition

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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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.

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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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- Definition

An excess of the fair value of the modified award over the fair value of the award immediately before the modification.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-based Compensation (Summary Of Stock-Based Compensation) (Details) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		12 Months Ended
	Apr. 30, 2020	Mar. 31, 2020	Dec. 31, 2019 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019	Dec. 31, 2018 USD ($)	Dec. 31, 2020 € / shares shares	Dec. 31, 2020 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			$ 305.8	$ 348.0		$ 206.0
Vesting period					10 years
Expiration period					10 years
Percent of annual inventive compensation							100.00%	100.00%
Other operating expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			3.9	7.6		4.4
SG&A expenses
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			301.9	340.4		201.6
Liberty Global Plc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			281.1	307.7		184.3
Performance-based incentive awards \| Liberty Global Plc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			134.5	127.4		50.8
Non-performance based incentive awards \| Liberty Global Plc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			107.6	134.1		90.1
Other \| Liberty Global Plc
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			39.0	46.2		43.4
Telenet share-based incentive awards \| Telenet
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			15.6	35.5		19.6
Other
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Allocated share-based compensation expense			$ 9.1	4.8		$ 2.1
Options \| Telenet
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares reserved for future issuance (in shares) \| shares							5,001,814	5,001,814
Awards outstanding (in EUR/USD per share) \| (per share)							€ 40.69	$ 49.74
SARs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period	10 years	7 years
Incremental share based compensation expense				$ 18.9