v3.26.3
Goodwill (Details)
$ in Millions
 9 Months Ended
Sep. 30, 2026
USD ($)
Goodwill [Roll Forward]  
Goodwill, net beginning balance $ 1,912.4
Goodwill, Acquired During Period 37.1
Currency translation (23.4)
Goodwill, net ending balance 1,926.1
Goodwill, Impaired, Accumulated Impairment Loss 573.6
Allegion Americas  
Goodwill [Roll Forward]  
Goodwill, net beginning balance 1,281.1
Goodwill, Acquired During Period 36.5
Currency translation (5.0)
Goodwill, net ending balance 1,312.6
Allegion International  
Goodwill [Roll Forward]  
Goodwill, net beginning balance 631.3
Goodwill, Acquired During Period 0.6
Currency translation (18.4)
Goodwill, net ending balance $ 613.5