v3.10.0.1

Debt and Capital Lease Obligations (Refinancing Transactions) (Details) £ in Millions				1 Months Ended							3 Months Ended	12 Months Ended
	Oct. 04, 2018 EUR (€)	Oct. 04, 2018 USD ($)	Jul. 31, 2018 USD ($)	Oct. 31, 2018 USD ($)	Aug. 31, 2018 EUR (€)	Aug. 31, 2018 USD ($)	Aug. 31, 2018 GBP (£)	May 31, 2018 USD ($)	Mar. 31, 2018 EUR (€)	Mar. 31, 2018 USD ($)	Oct. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 USD ($)	Aug. 31, 2018 USD ($)	May 31, 2018 EUR (€)	May 31, 2018 USD ($)
Debt Instrument [Line Items]
Outstanding principal amount												$ 32,178,000,000.0		$ 29,315,300,000
Dividends	€ 351,600,000	$ 404,800,000
Telenet
Debt Instrument [Line Items]
Dividends | €					€ 600,000,000.0
UPC Holding Senior Notes
Debt Instrument [Line Items]
Outstanding principal amount												1,313,400,000		$ 1,215,500,000
Senior Notes | Virgin Media
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment											$ 36,400,000
Payment for debt redemption premium											28,200,000
Write-off of unamortized debt discount and deferred financing cost											$ 8,200,000
Senior Notes | 2023 VM Dollar Senior Notes
Debt Instrument [Line Items]
Extinguishment of debt						$ 190,000,000.0
Senior Notes | 2023 VM Sterling Senior Notes
Debt Instrument [Line Items]
Extinguishment of debt				$ 340,000,000.0		318,600,000	£ 250.0
Stated interest rate of debt					7.00%										7.00%
Senior Notes | UPC Holding Senior Notes
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment												112,100,000	$ 77,100,000
Payment for debt redemption premium												84,300,000	57,200,000
Write-off of unamortized debt discount and deferred financing cost												27,800,000	19,900,000
Long-term Debt
Debt Instrument [Line Items]
Extinguishment of debt			$ 1,500,000,000
Long-term Debt | Virgin Media
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment												67,500,000	78,400,000
Payment for debt redemption premium												32,600,000	52,600,000
Write-off of unamortized debt discount and deferred financing cost												40,600,000	25,800,000
Write-off of unamortized debt discount (premium)												(7,000,000.0)
Third-party debt modification costs												1,300,000
Line of Credit | UPC Holding
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment						8,900,000
Payment for debt redemption premium						2,000,000.0
Write-off of unamortized debt discount and deferred financing cost						6,900,000
Line of Credit | Telenet
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment								$ 7,600,000		$ 21,300,000
Payment for debt redemption premium										17,300,000
Write-off of unamortized debt discount and deferred financing cost										4,000,000.0
Line of Credit | UPC Facility AR
Debt Instrument [Line Items]
Extinguishment of debt						330,000,000.0
Line of Credit | UPC Facility AS
Debt Instrument [Line Items]
Extinguishment of debt					€ 500,000,000.0	572,600,000
Line of Credit | UPC Facility AK
Debt Instrument [Line Items]
Extinguishment of debt					60,000,000.0	68,700,000
Line of Credit | Telenet Facility AL Add-on
Debt Instrument [Line Items]
Extinguishment of debt								300,000,000.0
Line of Credit | Telenet Credit Facility AL
Debt Instrument [Line Items]
Extinguishment of debt								1,300,000,000.0
Line of Credit | Telenet Credit Facility V
Debt Instrument [Line Items]
Extinguishment of debt									€ 250,000,000.0	286,300,000
Line of Credit | Telenet Credit Facility AM
Debt Instrument [Line Items]
Extinguishment of debt								$ 730,000,000.0
Medium-term Notes | Telenet
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment										2,600,000
Payment for debt redemption premium										2,000,000.0
Write-off of unamortized debt discount and deferred financing cost										600,000
Medium-term Notes | UPCB Finance IV Euro Notes
Debt Instrument [Line Items]
Extinguishment of debt | €					60,000,000.0
Outstanding principal amount | €					€ 600,000,000.0
Medium-term Notes | Telenet Credit Facility AB
Debt Instrument [Line Items]
Extinguishment of debt									€ 530,000,000.0	$ 607,000,000.0
Stated interest rate of debt										4.875%
Percentage of principal amount redeemed									10.00%	10.00%
Medium-term Notes | Telenet Finance VI Notes
Debt Instrument [Line Items]
Extinguishment of debt										$ 530,000,000.0
Percentage of principal amount redeemed									10.00%	10.00%
Medium-term Notes | Telenet Finance V Notes
Debt Instrument [Line Items]
Extinguishment of debt | €									€ 250,000,000.0
Stated interest rate of debt										6.75%
Senior Notes | 2023 VM Dollar Senior Notes
Debt Instrument [Line Items]
Original issue amount															$ 530,000,000.0
Stated interest rate of debt				6.375%	6.375%						6.375%				6.375%
Line of Credit | Telenet
Debt Instrument [Line Items]
Dividends					€ 600,000,000.0	$ 687,100,000
Line of Credit | UPC Facility AR
Debt Instrument [Line Items]
Outstanding principal amount															$ 1,975,000,000.0
Line of Credit | Telenet Credit Facility AO
Debt Instrument [Line Items]
Original issue amount																€ 730,000,000.0	$ 836,000,000.0
Original issue price																99.875%	99.875%
Line of Credit | UPC Facility AK
Debt Instrument [Line Items]
Stated interest rate of debt					4.00%										4.00%
Outstanding principal amount					€ 600,000,000.0										$ 687,100,000
Line of Credit | Telenet Facility AL Add-on
Debt Instrument [Line Items]
Original issue amount										$ 300,000,000.0
Line of Credit | Telenet Facility AN
Debt Instrument [Line Items]
Original issue amount																	$ 1,600,000,000.0
Original issue price																99.875%	99.875%
Line of Credit | Telenet Facility AN Add-on
Debt Instrument [Line Items]
Original issue amount															$ 475,000,000.0
Original issue price					98.50%										98.50%
Line of Credit | Telenet Facility AO Add-on
Debt Instrument [Line Items]
Original issue amount					€ 205,000,000.0										$ 234,800,000
Original issue price					98.00%										98.00%
Line of Credit | LIBOR | UPC Facility AR
Debt Instrument [Line Items]
Basis spread on variable rate					2.50%	2.50%	2.50%
Floor interest rate					0.00%										0.00%
Line of Credit | LIBOR | Telenet Credit Facility AL
Debt Instrument [Line Items]
Basis spread on variable rate									2.50%	2.50%
Floor interest rate										0.00%
Line of Credit | LIBOR | Telenet Facility AN
Debt Instrument [Line Items]
Basis spread on variable rate								2.25%
Floor interest rate																0.00%	0.00%
Line of Credit | EURIBOR | UPC Facility AS
Debt Instrument [Line Items]
Basis spread on variable rate					2.75%	2.75%	2.75%
Line of Credit | EURIBOR | Telenet Credit Facility AO
Debt Instrument [Line Items]
Basis spread on variable rate								2.50%
Floor interest rate																0.00%	0.00%
Line of Credit | EURIBOR | Telenet Credit Facility AM
Debt Instrument [Line Items]
Basis spread on variable rate								2.75%
Medium-term Notes | Telenet
Debt Instrument [Line Items]
Losses (gains) on debt modification and extinguishment												75,700,000	52,800,000
Payment for debt redemption premium												21,500,000	19,000,000.0
Write-off of unamortized debt discount and deferred financing cost												$ 54,200,000	$ 33,800,000

X

- Definition

Debt Instrument, Floor Interest Rate

+ References

No definition available.

+ Details

Name:	lbtya_DebtInstrumentFloorInterestRate
Namespace Prefix:	lbtya_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The issue price of the debt instrument, expressed as a percentage of the principal amount.

+ References

No definition available.

+ Details

Name:	lbtya_DebtInstrumentOriginalIssuePricePercentage
Namespace Prefix:	lbtya_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Payments For Debt Redemption Premium

+ References

No definition available.

+ Details

Name:	lbtya_PaymentsForDebtRedemptionPremium
Namespace Prefix:	lbtya_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Third-Party Debt Modification Costs

+ References

No definition available.

+ Details

Name:	lbtya_ThirdPartyDebtModificationCosts
Namespace Prefix:	lbtya_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Definition

Write-off of Unamortized Debt Discount (Premium)

+ References

No definition available.

+ Details

Name:	lbtya_WriteoffofUnamortizedDebtDiscountPremium
Namespace Prefix:	lbtya_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Write-off of Unamortized Debt Discount and Deferred Financing Cost

+ References

No definition available.

+ Details

Name:	lbtya_WriteoffofUnamortizedDebtDiscountandDeferredFinancingCost
Namespace Prefix:	lbtya_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6031897-161870

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 3: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

Name:	us-gaap_DebtInstrumentCarryingAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ 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 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
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_DebtInstrumentLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Percentage of principal amount of debt redeemed.

+ References

No definition available.

+ Details

Name:	us-gaap_DebtInstrumentRedemptionPricePercentageOfPrincipalAmountRedeemed
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared, for example, but not limited to, common and preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 405
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817

+ Details

Name:	us-gaap_Dividends
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

Name:	us-gaap_ExtinguishmentOfDebtAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12355-112629

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114001942&loc=d3e12317-112629

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

+ Details

Name:	us-gaap_GainsLossesOnExtinguishmentOfDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

Name:	dei_LegalEntityAxis=lbtya_TelenetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_UpcHoldingSeniorNotesDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ExtinguishmentOfDebtAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=lbtya_VirginMediaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_A2023VMDollarSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_A2023VMSterlingSeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ExtinguishmentOfDebtAxis=us-gaap_LongTermDebtMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ExtinguishmentOfDebtAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=lbtya_UpcHoldingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_UPCFacilityARMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_UPCFacilityASMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_UPCFacilityAKMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFacilityALAddonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetCreditFacilityALMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetCreditFacilityVMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetCreditFacilityAMMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_ExtinguishmentOfDebtAxis=us-gaap_MediumTermNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_UPCBFinanceIVEuroNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetCreditFacilityABMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFinanceVINotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFinanceVNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_SeniorNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_LineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetCreditFacilityAOMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFacilityANMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFacilityANAddonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_DebtInstrumentAxis=lbtya_TelenetFacilityAOAddonMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_VariableRateAxis=lbtya_EuriborMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_LongtermDebtTypeAxis=us-gaap_MediumTermNotesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: