Statement Of Changes In Equity [Abstract]

FORTERRA PLC - Filing #2019098

Concept	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2023-01-01 to 2023-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31	2022-01-01 to 2022-12-31
Statement of changes in equity [abstract]
Statement of changes in equity [line items]
Increase (decrease) through transfer to statutory reserve, equity	—	—	—	—	—	—	—	– GBP	– GBP	– GBP	23,900,000 GBP	– GBP	– GBP	23,900,000 GBP
Increase (decrease) through exercise of options, equity	– GBP	– GBP	2,600,000 GBP	– GBP	– GBP	2,600,000 GBP	– GBP	– GBP	600,000 GBP	– GBP	– GBP	– GBP	– GBP	600,000 GBP
Decrease (increase) through tax on share-based payment transactions, equity	– GBP	– GBP	– GBP	200,000 GBP	– GBP	200,000 GBP	– GBP	– GBP	– GBP	– GBP	– GBP	1,000,000 GBP	– GBP	1,000,000 GBP
Purchase of treasury shares	– GBP	– GBP	2,100,000 GBP	2,100,000 GBP	– GBP	– GBP	– GBP	– GBP	12,200,000 GBP	– GBP	– GBP	12,200,000 GBP	– GBP	– GBP
Sale or issue of treasury shares	– GBP	– GBP	1,100,000 GBP	1,100,000 GBP	– GBP	– GBP	– GBP	– GBP	400,000 GBP	– GBP	– GBP	400,000 GBP	– GBP	– GBP
Reduction of issued capital	—	—	—	—	—	—	—	200,000 GBP	– GBP	– GBP	– GBP	40,300,000 GBP	200,000 GBP	40,300,000 GBP