XML 50 R42.htm IDEA: XBRL DOCUMENT v3.23.2
Currency conversion (Detail)
6 Months Ended
Jun. 30, 2023
Jun. 30, 2022
Dec. 31, 2022
US dollar to Pound sterling      
Disclosure Of Foreign Currency Translation [line items]      
Average exchange rate 1.23 1.30  
Closing exchange rate 1.27   1.21
Euro to Pound sterling      
Disclosure Of Foreign Currency Translation [line items]      
Average exchange rate 1.14 1.19  
Closing exchange rate 1.16   1.13