v3.26.3
Business Segment Information (Summary of Operations by Reportable Segments) (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]        
Net revenues $ 1,172.6 $ 1,070.2 $ 3,357.7 $ 3,034.1
Cost of goods sold 624.4 580.4 1,837.5 1,655.3
Selling and administrative expenses 263.6 256.0 785.6 728.9
Operating income (loss) 284.6 233.8 734.6 649.9
Interest expense 24.2 26.6 73.2 75.9
Other income, net (7.4) (1.7) (5.8) (10.5)
Total earnings before income taxes 267.8 208.9 667.2 584.5
Operating Segments        
Segment Reporting [Line Items]        
Operating income (loss) 311.8 262.1 816.8 737.5
Operating Segments | Allegion Americas        
Segment Reporting [Line Items]        
Net revenues 942.4 844.0 2,670.9 2,423.3
Cost of goods sold 494.0 456.0 1,440.7 1,309.2
Selling and administrative expenses 153.8 145.6 453.7 423.7
Operating income (loss) 294.6 242.4 776.5 690.4
Depreciation, Depletion and Amortization 20.8 20.4 61.6 59.2
Operating Segments | Allegion International        
Segment Reporting [Line Items]        
Net revenues 230.2 226.2 686.8 610.8
Cost of goods sold 130.4 124.4 396.8 346.1
Selling and administrative expenses 82.6 82.1 249.7 217.6
Operating income (loss) 17.2 19.7 40.3 47.1
Depreciation, Depletion and Amortization 14.3 15.0 43.1 36.2
Corporate, Non-Segment        
Segment Reporting [Line Items]        
Operating income (loss) $ 27.2 $ 28.3 $ 82.2 $ 87.6