v3.26.3
Segments - Schedule of Segment Profit (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Segment Reporting [Line Items]        
Revenue $ 11,517 $ 10,221 $ 33,270 $ 28,813
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 104 52 99 50
Other income (loss) 8 3 25 10
Gain on disposition of real estate 184 36 490 55
Operating income 561 481 1,437 1,131
Operating segments        
Segment Reporting [Line Items]        
Revenue 11,517 10,221 33,270 28,813
Pass-through costs 4,691 4,212 13,761 12,095
Cost of revenue, excluding pass-through costs 4,701 4,092 13,446 11,416
Operating expenses and allocations 1,564 1,327 4,560 3,794
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 104 52 99 50
Other income (loss) 8 3 25 10
Gain on disposition of real estate 184 36 490 55
Other segment adjustments 135 98 536 322
Operating income 992 779 2,653 1,945
Corporate, other and eliminations        
Segment Reporting [Line Items]        
Revenue (18) (9) (47) (20)
Pass-through costs 0 0 0 0
Cost of revenue, excluding pass-through costs (1) (1) (5) 0
Operating expenses and allocations 208 182 614 542
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries (1) 1 (4) 24
Other income (loss) (1) 0 (2) (1)
Gain on disposition of real estate 12 3 32 3
Other segment adjustments 63 52 196 180
Operating income (152) (134) (434) (356)
Advisory Services | Operating segments        
Segment Reporting [Line Items]        
Revenue 2,441 2,199 6,771 5,817
Pass-through costs 16 14 32 39
Cost of revenue, excluding pass-through costs 1,482 1,297 4,021 3,403
Operating expenses and allocations 486 481 1,459 1,364
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 1 0 (2) 0
Other income (loss) 2 1 3 4
Gain on disposition of real estate 0 0 0 0
Other segment adjustments 7 (5) 31 14
Operating income 467 403 1,291 1,029
Building Operations & Experience | Operating segments        
Segment Reporting [Line Items]        
Revenue 6,856 5,842 20,033 17,068
Pass-through costs 3,641 3,118 10,688 9,265
Cost of revenue, excluding pass-through costs 2,507 2,125 7,339 6,110
Operating expenses and allocations 407 352 1,165 995
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 3 2 3 (14)
Other income (loss) 4 2 20 6
Gain on disposition of real estate 0 0 0 0
Other segment adjustments 41 38 100 84
Operating income 349 289 964 774
Project Management | Operating segments        
Segment Reporting [Line Items]        
Revenue 2,035 1,978 5,918 5,289
Pass-through costs 1,034 1,080 3,041 2,791
Cost of revenue, excluding pass-through costs 710 632 2,047 1,782
Operating expenses and allocations 132 120 393 353
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 0 0 0 0
Other income (loss) 1 0 2 1
Gain on disposition of real estate 0 0 0 0
Other segment adjustments 2 2 5 11
Operating income 162 148 444 375
Real Estate Investments | Operating segments        
Segment Reporting [Line Items]        
Revenue 203 211 595 659
Pass-through costs 0 0 0 0
Cost of revenue, excluding pass-through costs 3 39 44 121
Operating expenses and allocations 331 192 929 540
Other adjustments to segment operating profit (loss):        
Equity (loss) income from unconsolidated subsidiaries 101 49 102 40
Other income (loss) 2 0 2 0
Gain on disposition of real estate 172 33 458 52
Other segment adjustments 22 11 204 33
Operating income $ 166 $ 73 $ 388 $ 123