v3.26.1
BUSINESS SEGMENTS - Schedule of Segment Revenue, Segment Expenses, and Segment Profits (Details)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
segment
Jun. 30, 2025
USD ($)
Segment Reporting [Abstract]        
Number of reporting segments | segment     4  
Segment Reporting [Line Items]        
Revenue $ 7,071 $ 6,744 $ 13,725 $ 13,007
Depreciation, amortization, and other 115 53 169 104
General and administrative [1] 220 210 439 419
OPERATING INCOME 1,229 1,236 2,293 2,184
Total reportable segment revenue        
Segment Reporting [Line Items]        
Revenue 6,310 6,025 12,211 11,636
Total reportable segment revenue | U.S. & Canada        
Segment Reporting [Line Items]        
Revenue 5,263 4,962 10,218 9,660
Depreciation, amortization, and other 90 27 114 54
General and administrative 33 29 63 59
Other segment items (primarily non-operating income and expenses) (2) (2) (2) (3)
OPERATING INCOME 770 786 1,416 1,430
Total reportable segment revenue | EMEA        
Segment Reporting [Line Items]        
Revenue 610 655 1,117 1,169
Depreciation, amortization, and other 9 9 19 19
General and administrative 25 26 52 51
Other segment items (primarily non-operating income and expenses) (1) (2) (2) 0
OPERATING INCOME 144 157 216 231
Total reportable segment revenue | Greater China        
Segment Reporting [Line Items]        
Revenue 164 152 316 288
Depreciation, amortization, and other 2 3 5 5
General and administrative 13 12 25 24
Other segment items (primarily non-operating income and expenses) 0 0 (2) (1)
OPERATING INCOME 55 53 100 98
Total reportable segment revenue | APEC        
Segment Reporting [Line Items]        
Revenue 273 256 560 519
Depreciation, amortization, and other 2 2 4 4
General and administrative 15 15 31 29
Other segment items (primarily non-operating income and expenses) (2) (1) 0 1
OPERATING INCOME 69 76 140 156
Net fee revenues        
Segment Reporting [Line Items]        
Gross fee revenues 1,578 1,400 3,011 2,675
Contract investment amortization (31) (29) (66) (57)
Revenue 1,547 1,371 2,945 2,618
Net fee revenues | Total reportable segment revenue | U.S. & Canada        
Segment Reporting [Line Items]        
Gross fee revenues 906 800 1,679 1,509
Contract investment amortization (23) (21) (44) (41)
Revenue 883 779 1,635 1,468
Net fee revenues | Total reportable segment revenue | EMEA        
Segment Reporting [Line Items]        
Gross fee revenues 159 168 291 286
Contract investment amortization (5) (4) (10) (8)
Revenue 154 164 281 278
Net fee revenues | Total reportable segment revenue | Greater China        
Segment Reporting [Line Items]        
Gross fee revenues 68 64 137 124
Contract investment amortization 0 0 (1) 0
Revenue 68 64 136 124
Net fee revenues | Total reportable segment revenue | APEC        
Segment Reporting [Line Items]        
Gross fee revenues 86 83 190 181
Contract investment amortization (1) (2) (3) (3)
Revenue 85 81 187 178
Owned, leased, and other        
Segment Reporting [Line Items]        
Revenue 466 441 878 802
Operating costs [1] 417 363 794 695
Owned, leased, and other | Total reportable segment revenue | U.S. & Canada        
Segment Reporting [Line Items]        
Revenue 148 140 288 260
Operating costs 131 107 252 217
Owned, leased, and other | Total reportable segment revenue | EMEA        
Segment Reporting [Line Items]        
Revenue 158 164 274 278
Operating costs 135 142 255 257
Owned, leased, and other | Total reportable segment revenue | Greater China        
Segment Reporting [Line Items]        
Revenue 12 10 20 17
Operating costs 10 7 20 15
Owned, leased, and other | Total reportable segment revenue | APEC        
Segment Reporting [Line Items]        
Revenue 47 43 86 78
Operating costs 47 34 88 66
Reimbursements        
Segment Reporting [Line Items]        
Revenue 5,058 4,932 9,902 9,587
Operating costs 5,100 4,874 10,036 9,596
Reimbursements | Total reportable segment revenue | U.S. & Canada        
Segment Reporting [Line Items]        
Revenue 4,232 4,043 8,295 7,932
Operating costs 4,241 4,015 8,375 7,903
Reimbursements | Total reportable segment revenue | EMEA        
Segment Reporting [Line Items]        
Revenue 298 327 562 613
Operating costs 298 323 577 611
Reimbursements | Total reportable segment revenue | Greater China        
Segment Reporting [Line Items]        
Revenue 84 78 160 147
Operating costs 84 77 168 147
Reimbursements | Total reportable segment revenue | APEC        
Segment Reporting [Line Items]        
Revenue 141 132 287 263
Operating costs $ 142 $ 130 $ 297 $ 263
[1] The 2025 second quarter and 2025 first half reflect the reclassification of $35 million and $71 million, respectively, of other expenses previously reported under the “General, administrative, and other” caption to the “Owned, leased, and other expense” caption of our Income Statements to conform to our current presentation.