Disclosure Of Income Tax [Text Block]

Johnson Matthey PLC - Filing #1895979

Concept	2022-04-01 to 2023-03-31	As at 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2022-04-01 to 2023-03-31	2021-04-01 to 2022-03-31	2021-04-01 to 2022-03-31	2021-04-01 to 2022-03-31	2021-04-01 to 2022-03-31	2021-04-01 to 2022-03-31	2021-04-01 to 2022-03-31	As at 2022-03-31
Disclosure of income tax [text block]		—	—	—	—	—	—	—	—	—	—	—	—	—
Major components of tax expense (income) [abstract]
Tax expense (income)	80,000,000 GBP	—	—	—	—	—	—	—	—	—	—	—	79,000,000 GBP	—
Income tax relating to components of other comprehensive income [abstract]
Income tax relating to components of other comprehensive income	9,000,000 GBP	—	2 8 GBP	– GBP	– GBP	37,000,000 GBP	– GBP	– GBP	– GBP	35,000,000 GBP	10,000,000 GBP	– GBP	25,000,000 GBP	—
Disclosure of temporary difference, unused tax losses and unused tax credits [text block]	—	—	—	—	—	—	—	—	—	—	—	—	—	—
Disclosure of temporary difference, unused tax losses and unused tax credits [abstract]
Disclosure of temporary difference, unused tax losses and unused tax credits [line items]
Deferred tax assets and liabilities [abstract]
Deferred tax assets	—	121,000,000 GBP	—	—	—	—	—	—	—	—	—	—	—	98,000,000 GBP
Deferred tax liabilities	—	19,000,000 GBP	—	—	—	—	—	—	—	—	—	—	—	18,000,000 GBP
Reconciliation of changes in deferred tax liability (asset) [abstract]
Changes in deferred tax liability (asset) [abstract]
Reconciliation of accounting profit multiplied by applicable tax rates [abstract]