Share-based Compensation (Awards Outstanding and Exercisable) (Details)	Sep. 30, 2021 $ / 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)	25,757,426
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 27.06
Options exercisable (in shares)	12,557,002
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 30.64
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)	60,118,409
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 26.12
Options exercisable (in shares)	27,734,216
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 29.19
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)	2,722,067
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)	5,443,384
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)	1,306,731
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)	2,613,401
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)	1,675,974
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 31.14
Options exercisable (in shares)	1,388,812
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 32.80
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)	4,689,511
Options outstanding, weighted average exercise or base price (in dollars per shares) \| $ / shares	$ 28.45
Options exercisable (in shares)	4,115,209
Options exercisable, weighted average exercise price or base price (in dollars per shares) \| $ / shares	$ 23.32
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)	74,193
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)	148,583
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)	37,510
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)	75,016

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.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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=120381028&loc=d3e5070-113901

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No definition available.

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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.

+ References

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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- Definition

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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