v3.10.0.1

Equity (Schedule of Outstanding Share-Based Compensation Awards) (Details) - shares | Dec. 31, 2018 | Dec. 31, 2017
--- | --- | ---
Class B |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common reserved for issuance (in shares) | 11,099,593 |
Options | Class A |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Awards outstanding (in shares) | 580,254 | 580,481
Options | Class C |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Awards outstanding (in shares) | 2,667,506 | 2,725,566
SARs | Class A |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common reserved for issuance (in shares) | 15,308,562 |
SARs | Class C |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Awards outstanding (in shares) | 34,401,980 | 31,305,136
Common reserved for issuance (in shares) | 34,401,980 |
PSUs, PGUs, RSUs | Class A |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common reserved for issuance (in shares) | 3,487,018 |
PSUs, PGUs, RSUs | Class C |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |
Common reserved for issuance (in shares) | 6,976,788 |

X
- Definition Aggregate number of common shares reserved for future issuance. + 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 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_CommonStockCapitalSharesReservedForFutureIssuance
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- 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. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of options outstanding, including both vested and non-vested options. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1)(i)-(ii) -URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_EmployeeStockOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_StockAppreciationRightsSARSMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=lbtya_PSUsPGUsandRSUsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |