Share-based Compensation (Awards Outstanding and Exercisable) (Details)	Mar. 31, 2020 $ / shares shares
Held by Liberty Global employees: \| Options and SARs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	20,474,598
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 30.13
Options exercisable (in shares)	11,845,481
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 32.43
Held by Liberty Global employees: \| Options and SARs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	46,274,632
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 28.71
Options exercisable (in shares)	28,610,972
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 30.29
Held by Liberty Global employees: \| RSUs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	471,979
Held by Liberty Global employees: \| RSUs \| Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	0
Held by Liberty Global employees: \| RSUs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	938,931
Held by Liberty Global employees: \| PSUs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	3,395,295
Held by Liberty Global employees: \| PSUs \| Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	1,330,000
Held by Liberty Global employees: \| PSUs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	6,790,516
Held by former Liberty Global employees: \| Options and SARs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	1,494,806
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 33.98
Options exercisable (in shares)	1,440,609
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 33.94
Held by former Liberty Global employees: \| Options and SARs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding (in shares)	3,344,700
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 32.09
Options exercisable (in shares)	3,236,327
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 32.02
Held by former Liberty Global employees: \| RSUs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	2,191
Held by former Liberty Global employees: \| RSUs \| Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	0
Held by former Liberty Global employees: \| RSUs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	4,365
Held by former Liberty Global employees: \| PSUs \| Class A
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	47,671
Held by former Liberty Global employees: \| PSUs \| Class B
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	0
Held by former Liberty Global employees: \| PSUs \| Class C
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Other than options outstanding (in shares)	95,340

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

+ References

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

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

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