v3.25.4
Financial Instruments - Additional Information (Detail)
shares in Millions, $ in Millions, £ in Billions
 1 Months Ended 12 Months Ended
May 31, 2025
USD ($)
May 31, 2025
CAD ($)
Mar. 31, 2025
Dec. 31, 2024
USD ($)
Sep. 30, 2024
USD ($)
Dec. 31, 2025
USD ($)
Basispoint
Dec. 31, 2024
USD ($)
shares
Dec. 31, 2024
CAD ($)
Dec. 31, 2024
GBP (£)
Dec. 31, 2023
USD ($)
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings       $ 2,820,000,000   $ 2,123,000,000 $ 2,820,000,000      
Other financial liabilities, non-current       0   $ 16,000,000 0      
Derivatives hedge ratio           1:1        
Solicitation fees           $ 4,000,000        
Transaction costs           8,000,000        
Cash collateral       0   7,000,000 0      
Proceeds from (payment to) settlement of foreign exchange contracts             24,000,000      
Losses on change in fair value of derivatives           (8,000,000) 99,000,000      
Foreign currency translation adjustments to OCI           $ 269,000,000 (173,000,000)      
Percentage strengthening of US dollar against other foreign currencies           10.00%        
Cash and cash equivalents       1,968,000,000   $ 511,000,000 1,968,000,000     $ 1,298,000,000
Short-term Investments, cash and cash equivalents       1,095,000,000   $ 235,000,000 1,095,000,000      
Percentage of cash and cash equivalents held by a rated institutions           96.00%        
Trade and other receivables       1,087,000,000   $ 1,143,000,000 1,087,000,000      
Other financial assets       378,000,000   392,000,000 378,000,000      
Gross loan commitments           2,000,000,000        
Due from indemnification arrangement       272,000,000   288,000,000 272,000,000      
Other receivables       29,000,000   32,000,000 29,000,000      
Financial assets at fair value through other comprehensive income       99,000,000   168,000,000 99,000,000      
Cash consideration received on disposal of business           254,000,000 326,000,000      
Derivative financial liabilities       21,000,000   16,000,000 21,000,000      
Level 3 [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Short-term Investments, cash and cash equivalents       0   0 0      
Financial assets at fair value through other comprehensive income       98,000,000   168,000,000 98,000,000      
Increase in financial assets at fair value through other comprehensive income           46,000,000        
Contingent Receivables [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Other receivables       88,000,000   84,000,000 88,000,000      
Cash consideration received on disposal of business       88,000,000            
Thomson Reuters Corporation [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Proportion of ownership interest in subsidiary     100.00%              
At fair value [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Derivative financial liabilities       21,000,000   16,000,000 21,000,000      
Other finance income [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Losses on change in fair value of derivatives             2,000,000      
Fixed-to-floating interest rate swaps [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Other financial liabilities, non-current           $ 16,000,000        
Fixed-to-floating interest rate swaps notional amount           410,000,000        
Cash collateral           $ 7,000,000        
Losses on change in fair value of derivatives           16,000,000 0      
Foreign exchange contracts settlement [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Derivative financial assets       0   $ 0 0      
Notional amount       1,600,000,000     1,600,000,000   £ 1.2  
Proceeds from (payment to) settlement of foreign exchange contracts             $ 24,000,000      
Foreign exchange contracts settlement [member] | LSEG [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Number of shares sold that relate to company ownership | shares             16.0      
Interest rate risk [member] | SOFR [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Percentage of reasonably possible increase in unobservable input, assets | Basispoint           100        
Percentage of reasonably possible decrease in unobservable input assets | Basispoint           100        
Increase decrease in fair value measurement due to reasonably possible increase in unobservable inputs recognized in profit or loss before tax assets           $ 4,000,000        
Interest rate risk [member] | Interest bearing assets [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Short-term Investments, cash and cash equivalents           $ 235,000,000        
Percentage of reasonably possible increase in unobservable input, assets | Basispoint           100        
Percentage of reasonably possible decrease in unobservable input assets | Basispoint           100        
Increase decrease in fair value measurement due to reasonably possible increase in unobservable inputs recognized in profit or loss before tax assets           $ 2,000,000        
Credit risk [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Cash and cash equivalents       1,968,000,000   511,000,000 $ 1,968,000,000      
Trade and other receivables       $ 1,087,000,000   $ 1,143,000,000 $ 1,087,000,000      
3.85% Notes, due 2024 [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings         $ 450,000,000          
Borrowings, interest rate         3.85%          
Repayments of current borrowings         $ 242,000,000          
2.239% Notes, due 2025 [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings, interest rate 2.239% 2.239%   2.239%     2.239% 2.239% 2.239%  
Notional amount               $ 1,400    
Maturity date             2025      
Repayments of current borrowings $ 999,000,000 $ 1,400                
Derivative financial liabilities       $ 21,000,000     $ 21,000,000      
2.239% Notes, due 2025 [member] | At fair value [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Derivative financial liabilities       $ 21,000,000     $ 21,000,000      
4.50% Notes, due 2043 [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings, interest rate       4.50%   4.50% 4.50% 4.50% 4.50%  
Notional amount       $ 119,000,000   $ 119,000,000 $ 119,000,000      
Maturity date           2043 2043      
Derivative financial liabilities       0   $ 3,000,000 $ 0      
4.50% Notes, due 2043 [member] | At fair value [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Derivative financial liabilities       $ 0   $ 3,000,000 $ 0      
4.50% Notes, due 2043 [member] | Fixed-to-floating interest rate swaps [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings, interest rate           4.50%        
Notional amount           $ 119,000,000        
Fixed-to-floating interest rate swaps notional amount           80,000,000        
Maturity date           May 2043        
5.65% Notes, due 2043 [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings, interest rate       5.65%   5.65% 5.65% 5.65% 5.65%  
Notional amount       $ 350,000,000   $ 350,000,000 $ 350,000,000      
Maturity date           2043 2043      
Derivative financial liabilities       0   $ 13,000,000 $ 0      
5.65% Notes, due 2043 [member] | At fair value [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Derivative financial liabilities       0   $ 13,000,000 0      
5.65% Notes, due 2043 [member] | Fixed-to-floating interest rate swaps [member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings, interest rate           5.65%        
Notional amount           $ 350,000,000        
Fixed-to-floating interest rate swaps notional amount           330,000,000        
Maturity date           November 2043        
Commercial Paper [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings       0   $ 295,000,000 0      
Commercial paper programs           2,000,000,000        
Amended Credit Facility Maturities In November 2030 [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Borrowings       $ 0   0 $ 0      
Gross loan commitments           $ 2,000,000,000        
Basis point adjustment to reference interest rate           9.2        
Additional commitment from lenders           $ 600,000,000        
Maximum credit facility agreement           2,600,000,000        
Purchase price           $ 500,000,000        
Net debt to adjusted EBITDA           0.6        
Amended Credit Facility Maturities In November 2030 [Member] | Top of Range [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Required ratio of net debt to ebitda           4.5        
Amended Credit Facility Maturities In November 2030 [Member] | Scenario Forecast [Member]                    
Disclosure of detailed information about financial instruments [Line Items]                    
Required ratio of net debt to ebitda           5