v3.26.3
Revenue Recognition - Disaggregation of Revenue (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Disaggregation of Revenue [Line Items]        
Revenue $ 4,840.0 $ 4,634.4 $ 14,210.6 $ 13,244.0
Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 4,840.0 4,634.4 14,210.6 13,244.0
Intercompany Eliminations        
Disaggregation of Revenue [Line Items]        
Revenue (10.1) (7.1) (22.2) (24.4)
Americas | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 1,246.7 1,098.7 3,574.6 3,215.4
Americas | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 1,224.7 1,079.5 3,509.5 3,157.5
Americas | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 22.0 19.2 65.1 57.9
Americas | United States | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 728.8 [1] 690.8 [2] 2,098.0 [3],[4] 2,053.7 [5]
Americas | United States | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 714.4 676.6 2,055.3 2,010.4
Americas | United States | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 14.4 14.2 42.7 43.3
Americas | Other Americas | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 517.9 407.9 1,476.6 1,161.7
Americas | Other Americas | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 510.3 402.9 1,454.2 1,147.1
Americas | Other Americas | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 7.6 5.0 22.4 14.6
Americas | Staffing and Interim        
Disaggregation of Revenue [Line Items]        
Revenue 1,140.1 996.1 3,257.4 2,910.8
Americas | Staffing and Interim | United States        
Disaggregation of Revenue [Line Items]        
Revenue 657.8 617.4 1,880.7 1,833.1
Americas | Staffing and Interim | Other Americas        
Disaggregation of Revenue [Line Items]        
Revenue 482.3 378.7 1,376.7 1,077.7
Americas | Outcome-Based Solutions and Consulting        
Disaggregation of Revenue [Line Items]        
Revenue 21.5 19.6 60.4 56.2
Americas | Outcome-Based Solutions and Consulting | United States        
Disaggregation of Revenue [Line Items]        
Revenue 2.3 2.8 6.4 8.2
Americas | Outcome-Based Solutions and Consulting | Other Americas        
Disaggregation of Revenue [Line Items]        
Revenue 19.2 16.8 54.0 48.0
Americas | Permanent Recruitment        
Disaggregation of Revenue [Line Items]        
Revenue 39.9 36.6 117.2 110.1
Americas | Permanent Recruitment | United States        
Disaggregation of Revenue [Line Items]        
Revenue 28.4 27.4 84.5 83.0
Americas | Permanent Recruitment | Other Americas        
Disaggregation of Revenue [Line Items]        
Revenue 11.5 9.2 32.7 27.1
Americas | Other        
Disaggregation of Revenue [Line Items]        
Revenue 45.2 46.4 139.6 138.3
Americas | Other | United States        
Disaggregation of Revenue [Line Items]        
Revenue 40.3 43.2 126.4 129.4
Americas | Other | Other Americas        
Disaggregation of Revenue [Line Items]        
Revenue 4.9 3.2 13.2 8.9
Southern Europe | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 2,227.9 2,205.5 6,637.9 6,188.8
Southern Europe | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 2,197.9 2,175.4 6,535.6 6,092.8
Southern Europe | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 30.0 30.1 102.3 96.0
Southern Europe | France | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 1,132.9 1,173.5 3,379.1 3,288.5
Southern Europe | France | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 1,125.6 1,164.3 3,351.8 3,258.5
Southern Europe | France | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 7.3 9.2 27.3 30.0
Southern Europe | Italy | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 483.1 462.5 1,479.7 1,336.2
Southern Europe | Italy | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 473.2 452.2 1,443.9 1,302.7
Southern Europe | Italy | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 9.9 10.3 35.8 33.5
Southern Europe | Other Southern Europe | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 611.9 569.5 1,779.1 1,564.1
Southern Europe | Other Southern Europe | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 599.1 558.9 1,739.9 1,531.6
Southern Europe | Other Southern Europe | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 12.8 10.6 39.2 32.5
Southern Europe | Staffing and Interim        
Disaggregation of Revenue [Line Items]        
Revenue 1,999.9 1,976.1 5,919.0 5,502.1
Southern Europe | Staffing and Interim | France        
Disaggregation of Revenue [Line Items]        
Revenue 1,046.4 1,077.6 3,102.7 2,999.7
Southern Europe | Staffing and Interim | Italy        
Disaggregation of Revenue [Line Items]        
Revenue 452.5 434.1 1,378.8 1,244.6
Southern Europe | Staffing and Interim | Other Southern Europe        
Disaggregation of Revenue [Line Items]        
Revenue 501.0 464.4 1,437.5 1,257.8
Southern Europe | Outcome-Based Solutions and Consulting        
Disaggregation of Revenue [Line Items]        
Revenue 162.8 158.7 497.6 465.6
Southern Europe | Outcome-Based Solutions and Consulting | France        
Disaggregation of Revenue [Line Items]        
Revenue 61.6 65.8 190.0 195.4
Southern Europe | Outcome-Based Solutions and Consulting | Italy        
Disaggregation of Revenue [Line Items]        
Revenue 13.0 11.2 41.8 35.2
Southern Europe | Outcome-Based Solutions and Consulting | Other Southern Europe        
Disaggregation of Revenue [Line Items]        
Revenue 88.2 81.7 265.8 235.0
Southern Europe | Permanent Recruitment        
Disaggregation of Revenue [Line Items]        
Revenue 35.4 34.9 118.5 110.6
Southern Europe | Permanent Recruitment | France        
Disaggregation of Revenue [Line Items]        
Revenue 8.2 10.1 29.6 32.9
Southern Europe | Permanent Recruitment | Italy        
Disaggregation of Revenue [Line Items]        
Revenue 10.5 11.0 38.0 35.9
Southern Europe | Permanent Recruitment | Other Southern Europe        
Disaggregation of Revenue [Line Items]        
Revenue 16.7 13.8 50.9 41.8
Southern Europe | Other        
Disaggregation of Revenue [Line Items]        
Revenue 29.8   102.8 110.5
Southern Europe | Other | France        
Disaggregation of Revenue [Line Items]        
Revenue 16.7 20.0 56.8 60.5
Southern Europe | Other | Italy        
Disaggregation of Revenue [Line Items]        
Revenue 7.1 6.2 21.1 20.5
Southern Europe | Other | Other Southern Europe        
Disaggregation of Revenue [Line Items]        
Revenue 6.0 9.6 24.9 29.5
Northern Europe | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 860.6 816.8 2,476.2 2,342.0
Northern Europe | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 844.9 799.2 2,427.0 2,283.3
Northern Europe | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 15.7 17.6 49.2 58.7
Northern Europe | Staffing and Interim        
Disaggregation of Revenue [Line Items]        
Revenue 759.7 712.1 2,154.3 2,016.0
Northern Europe | Outcome-Based Solutions and Consulting        
Disaggregation of Revenue [Line Items]        
Revenue 51.5 56.7 172.6 172.3
Northern Europe | Permanent Recruitment        
Disaggregation of Revenue [Line Items]        
Revenue 23.3 23.5 71.8 77.5
Northern Europe | Other        
Disaggregation of Revenue [Line Items]        
Revenue 26.1 24.5 77.5 76.2
APME | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 514.9 520.5 1,544.1 1,522.2
APME | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 504.8 509.4 1,512.8 1,489.5
APME | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 10.1 11.1 31.3 32.7
APME | Staffing and Interim        
Disaggregation of Revenue [Line Items]        
Revenue 435.3 433.9 1,304.5 1,267.4
APME | Outcome-Based Solutions and Consulting        
Disaggregation of Revenue [Line Items]        
Revenue 58.2 62.9 174.3 187.6
APME | Permanent Recruitment        
Disaggregation of Revenue [Line Items]        
Revenue 11.7 12.8 36.3 37.8
APME | Other        
Disaggregation of Revenue [Line Items]        
Revenue 9.7 10.9 29.0 29.4
Northern Europe and APME | Reportable subsegments        
Disaggregation of Revenue [Line Items]        
Revenue 4,850.1 4,641.5 14,232.8 13,268.4
Northern Europe and APME | Services transferred over time        
Disaggregation of Revenue [Line Items]        
Revenue 4,772.3 4,563.5 13,984.9 13,023.1
Northern Europe and APME | Services transferred at a point in time        
Disaggregation of Revenue [Line Items]        
Revenue 77.8 78.0 247.9 245.3
Northern Europe and APME | Staffing and Interim        
Disaggregation of Revenue [Line Items]        
Revenue 4,335.0 4,118.2 12,635.2 11,696.3
Northern Europe and APME | Outcome-Based Solutions and Consulting        
Disaggregation of Revenue [Line Items]        
Revenue 294.0 297.9 904.9 881.7
Northern Europe and APME | Permanent Recruitment        
Disaggregation of Revenue [Line Items]        
Revenue 110.3 107.8 343.8 336.0
Northern Europe and APME | Other        
Disaggregation of Revenue [Line Items]        
Revenue $ 110.8 $ 117.6 $ 348.9 $ 354.4
[1] The United States revenues above represent revenues from our company-owned branches and franchise fees received from our franchise operations, which were $2.4 for the three months ended September 30, 2026.
[2] The United States revenues above represent revenues from our company-owned branches and franchise fees received from our franchise operations, which were $2.7 for the three months ended September 30, 2025.
[3] The United States Selling and Administrative Expenses and OUP included a $28.3 gain on the sale of our Jefferson Wells U.S. business.
[4] The United States revenues above represent revenues from our company-owned branches and franchise fees received from our franchise operations, which were $7.5 for the nine months ended September 30, 2026.
[5] The United States revenues above represent revenues from our company-owned branches and franchise fees received from our franchise operations, which were $7.5 for the nine months ended September 30, 2025.