Additional basis points on discount rate used to calculate redemption premium on debt instrument.

No definition available.

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- Definition

Debt Instrument, Floor Interest Rate

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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

+ References

No definition available.

+ Details

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

- Definition

Payments For Debt Redemption Premium

+ References

No definition available.

+ Details

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

- Definition

Special Purpose Financing Entity Ownership by Third Party

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Write-off of Unamortized Debt Discount (Premium)

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Write-off of Unamortized Debt Discount and Deferred Financing Cost

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

+ Details

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

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-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

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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.

+ References

No definition available.

+ Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph e
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 50
-Section 40
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12317-112629

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Subparagraph (b)
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-SubTopic 50
-Section 40
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=49170532&loc=d3e12355-112629

+ Details

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

- Definition

Amount of cash outflow for cost from early extinguishment and prepayment of debt. Includes, but is not limited to, third-party cost, premium paid, and other fee paid to lender directly for debt extinguishment or debt prepayment. Excludes accrued interest.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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Debt and Capital Lease Obligations (C&W Refinancing Transactions) (Details) € in Millions	1 Months Ended			9 Months Ended
	Aug. 31, 2017 USD ($)	May 31, 2017 EUR (€)	May 31, 2017 USD ($)	Sep. 30, 2017	Jul. 31, 2017 USD ($)
C&W Term Loans [Member] \| Medium-term Notes [Member]
Debt Instrument [Line Items]
Extinguishment of debt \| €		€ 1,100.0
Loss on debt modification and extinguishment			$ 24,900,000
Write-off of unamortized discounts and deferred financing costs			22,700,000
Payment for third-party costs			2,200,000
Columbus Senior Notes [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Extinguishment of debt	$ 1,250,000,000.0
Loss on debt modification and extinguishment	25,800,000
Payments for debt redemption premium	85,100,000
Write-off of unamortized debt discount (premium)	(59,300,000)
C&W [Member] \| Medium-term Notes [Member] \| C&W Term Loan B-3 Facility [Member]
Debt Instrument [Line Items]
Principal amount of debt			$ 1,125,000,000.0
Issue price percentage			99.50%
C&W [Member] \| Medium-term Notes [Member] \| C&W Term Loan B-3 Facility [Member] \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		3.50%	3.50%
Floor rate			0.00%
C&W [Member] \| Medium-term Notes [Member] \| C&W Term Loan B-3 Facility Add-on [Member]
Debt Instrument [Line Items]
Principal amount of debt					$ 700,000,000.0
Issue price percentage					99.50%
C&W Senior Financing [Member]
Debt Instrument [Line Items]
Special purpose financing entity ownership by third party				100.00%
C&W Senior Financing [Member] \| Senior Notes [Member] \| 2027 C&W Senior Notes [Member]
Debt Instrument [Line Items]
Principal amount of debt	$ 700,000,000.0
Interest rate	6.875%
Additional basis points used to determine redemption premium				0.50%
C&W Senior Financing [Member] \| Senior Notes [Member] \| 2027 C&W Senior Notes [Member] \| 2022
Debt Instrument [Line Items]
Redemption price				103.438%
C&W Senior Financing [Member] \| Senior Notes [Member] \| 2027 C&W Senior Notes [Member] \| 2023
Debt Instrument [Line Items]
Redemption price				101.719%
C&W Senior Financing [Member] \| Senior Notes [Member] \| 2027 C&W Senior Notes [Member] \| 2024
Debt Instrument [Line Items]
Redemption price				100.859%
C&W Senior Financing [Member] \| Senior Notes [Member] \| 2027 C&W Senior Notes [Member] \| 2025 and thereafter
Debt Instrument [Line Items]
Redemption price				100.00%