Statement Of Comprehensive Income [Abstract]

Johnson Matthey PLC - Filing #1656099

Concept	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	2020-04-01 to 2021-03-31	2020-04-01 to 2021-03-31	2020-04-01 to 2021-03-31	2020-04-01 to 2021-03-31	2020-04-01 to 2021-03-31	2020-04-01 to 2021-03-31
Statement of comprehensive income [abstract]
Profit (loss)	– GBP	– GBP	101,000,000 GBP	– GBP	– GBP	101,000,000 GBP	– GBP	– GBP	– GBP	– GBP	205,000,000 GBP	205,000,000 GBP
Other comprehensive income [abstract]
Other comprehensive income that will not be reclassified to profit or loss, net of tax	—	—	—	—	—	137,000,000 GBP	—	—	—	—	—	108,000,000 GBP
Components of other comprehensive income that will be reclassified to profit or loss, net of tax [abstract]
Exchange differences on translation [abstract]
Other comprehensive income, net of tax, exchange differences on translation of foreign operations	– GBP	– GBP	– GBP	80,000,000 GBP	– GBP	80,000,000 GBP	– GBP	1 62 GBP	– GBP	– GBP	– GBP	1 62 GBP
Cash flow hedges [abstract]
Other comprehensive income, net of tax, cash flow hedges	– GBP	– GBP	– GBP	36,000,000 GBP	– GBP	3 6 GBP	– GBP	3,000,000 GBP	– GBP	– GBP	– GBP	3,000,000 GBP
Hedges of net investment in foreign operations [abstract]
Other comprehensive income, net of tax, hedges of net investments in foreign operations	– GBP	– GBP	– GBP	2,000,000 GBP	– GBP	2,000,000 GBP	– GBP	12,000,000 GBP	– GBP	– GBP	– GBP	12,000,000 GBP
Other comprehensive income that will be reclassified to profit or loss, net of tax	—	—	—	—	—	52,000,000 GBP	—	—	—	—	—	147,000,000 GBP
Other comprehensive income	—	—	—	—	—	189,000,000 GBP	—	—	—	—	—	255,000,000 GBP
Comprehensive income	– GBP	– GBP	41,000,000 GBP	47,000,000 GBP	– GBP	88,000,000 GBP	– GBP	1 42 GBP	– GBP	– GBP	92,000,000 GBP	50,000,000 GBP