v3.24.0.1
Intangible assets and goodwill - Narrative (Details)
 3 Months Ended 12 Months Ended
Jan. 03, 2023
USD ($)
Dec. 31, 2023
USD ($)
Dec. 31, 2023
USD ($)
business
Dec. 31, 2022
USD ($)
Dec. 31, 2021
USD ($)
Intangible assets and goodwill          
Goodwill impairment     $ 0 $ 0 $ 0
Period over which management has projected cash flows     5 years    
Discount rates applied to cash flow projections   9.80% 9.80% 9.50% 9.00%
Growth rates applied to cash flow projections   3.00% 3.00% 3.00% 3.00%
Goodwill   $ 1,963,000,000 $ 1,963,000,000 $ 1,350,000,000  
WillowTree          
Intangible assets and goodwill          
Ownership interest in businesses acquired 86.00%        
Ownership interest maintained by acquired entity management 0.14        
Percentage of subordinate voting share 0.70        
Net assets acquired $ 1,175,000,000 1,175,000,000 1,175,000,000    
Cash transferred 856,000,000 856,000,000 856,000,000    
Business acquisition consideration transferred, value of shares 125,000,000   125,000,000    
Provisions 194,000,000   194,000,000    
Net identifiable assets acquired   576,000,000 576,000,000    
Goodwill $ 97,000,000        
Revenue arising from contracts with customers     186,000,000    
Net income     $ (93,000,000)    
WillowTree | Written Put Options Related to Retained Equity Interests          
Intangible assets and goodwill          
Future exercise period     3 years    
Other          
Intangible assets and goodwill          
Net assets acquired   2,000,000 $ 2,000,000    
Cash transferred   1,000,000 1,000,000    
Business acquisition consideration transferred, value of shares     $ 0    
Number of businesses acquired | business     2    
Provisions     $ 1,000,000    
Net identifiable assets acquired   2,000,000 2,000,000    
Goodwill   0 0    
Revenue arising from contracts with customers     4,000,000    
Net income   0 0    
Increase in revenue   $ 1,000,000      
Other | Maximum          
Intangible assets and goodwill          
Earn-out payout     $ 12,000,000