| Document and Entity Information | Aug. 31, 2021 |
| Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Aug. 31, 2021 |
| Entity Registrant Name | Liberty Global plc |
| Entity Central Index Key | 0001570585 |
| Amendment Flag | false |
| Entity Incorporation, State or Country Code | X0 |
| Entity File Number | 001-35961 |
| Entity Tax Identification Number | 98-1112770 |
| Entity Address, Address Line One | Griffin House |
| Entity Address, Address Line Two | 161 Hammersmith Rd |
| Entity Address, City or Town | London |
| Entity Address, Country | GB |
| Entity Address, Postal Zip Code | W6 8BS |
| Country Region | 44 |
| City Area Code | 208 |
| Local Phone Number | 483.6449 |
| Written Communications | false |
| Soliciting Material | false |
| Pre-commencement Tender Offer | false |
| Pre-commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Common Class A [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Class A ordinary shares |
| Trading Symbol | LBTYA |
| Security Exchange Name | NASDAQ |
| Common Class B [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Class B ordinary shares |
| Trading Symbol | LBTYB |
| Security Exchange Name | NASDAQ |
| Common Class C [Member] | |
| Entity Information [Line Items] | |
| Title of 12(b) Security | Class C ordinary shares |
| Trading Symbol | LBTYK |
| Security Exchange Name | NASDAQ |
