v3.26.1
Related party (Details) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 22, 2025
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Related Party Transaction [Line Items]              
Total Revenues   $ 3,494 $ 2,181 $ 3,218 $ 2,089 $ 5,675 $ 5,307
Cost of revenues:   2,501 1,973 2,277 1,852 4,474 4,129
Selling, general and administrative expenses   283 285 286 243 568 529
Interest expense   94   143   180 275
Interest income   5   22   13 36
Interest expense, debt   $ 78   54   150 65
Net transfers to Parent     $ 0   $ 96 0 98
Equity contribution from Holcim related to the settlement of Related-party notes payable           $ 0 1,999
Other non-cash activities with Parent, net             25
Related Party              
Related Party Transaction [Line Items]              
Total Revenues       8     33
Cost of revenues:       8     16
Allocations for management costs       33     60
Selling, general and administrative expenses       25     44
Interest expense       1     1
Interest income       7     12
Borrowing arrangements $ 7,645            
Interest expense, debt       75     183
Related Party | Products And Services Purchased From Parent              
Related Party Transaction [Line Items]              
Cost of revenues:       $ 38     $ 69
Related Party | Related Party Notes Settled Through Dividend              
Related Party Transaction [Line Items]              
Related party, amounts of transaction 5,646            
Related Party | Related Party Notes Settled As Equity Contribution              
Related Party Transaction [Line Items]              
Related party, amounts of transaction $ 1,999            
Minimum | Related Party              
Related Party Transaction [Line Items]              
Transition services agreement, term           1 year  
Tax matters agreement, term           2 years  
Maximum | Related Party              
Related Party Transaction [Line Items]              
Transition services agreement, term           2 years  
Tax matters agreement, term           5 years