| Document and Entity Information | Dec. 04, 2024 |
| Document And Entity Information [Line Items] | |
| Document Type | 8-K |
| Document Period End Date | Dec. 04, 2024 |
| Entity Registrant Name | Allegion plc |
| Entity Incorporation State Country Code | L2 |
| Entity File Number | 001-35971 |
| Entity Tax Identification Number | 98-1108930 |
| Entity Address Address Line 1 | Block D |
| Entity Address Address Line 2 | Iveagh Court |
| Entity Address Address Line 3 | Harcourt Road |
| Entity Address City Or Town | Dublin 2 |
| Entity Address Country | IE |
| Entity Address Postal Zip Code | D02 VH94 |
| Country Region | 353 |
| City Area Code | 1 |
| Local Phone Number | 2546200 |
| Written Communications | false |
| Soliciting Material | false |
| Pre Commencement Tender Offer | false |
| Pre Commencement Issuer Tender Offer | false |
| Entity Emerging Growth Company | false |
| Entity Central Index Key | 0001579241 |
| Amendment Flag | false |
| Common Stock [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | Ordinary shares, par value $0.01 per share |
| Trading Symbol | ALLE |
| Security Exchange Name | NYSE |
| Three Point Five% Senior Notes Due 2029 [Member] | |
| Document And Entity Information [Line Items] | |
| Security 12b Title | 3.500% Senior Notes due 2029 |
| Trading Symbol | ALLE 3 1⁄2 |
| Security Exchange Name | NYSE |
