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Repurchase of ordinary shares (in shares) Treasury Stock, Shares, Acquired Intangible amortization expense, year one Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One Disaggregation of Revenue [Table] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table] Net periodic pension and postretirement benefit cost, less service cost Net Periodic Defined Benefits Expense (Reversal of Expense), Excluding Service Cost Component Debt repayments Proceeds from (Repayments of) Other Debt Entity Tax Identification Number Entity Tax Identification Number Tax benefit Share-Based Payment Arrangement, Expense, Tax Benefit Lessee, Lease, Description [Table] Lessee, Operating Lease, Liability, Maturity [Table] Lessee, Lease, Description [Table] Payments for Restructuring Payments for Restructuring Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents Cash and cash equivalents - beginning of period Cash and cash equivalents - end of period 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Cover [Abstract] Dividend yield Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Expected Dividend Rate Derivative Contract Type Derivative Contract [Domain] Currency translation Goodwill, Foreign Currency Translation, Gain (Loss) Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] Total liabilities and equity Liabilities and Equity Lessee, Operating Lease Asset and Liability, and Other Information Assets and Liabilities, Lessee [Table Text Block] Assets and Liabilities, Lessee Stock options Share-Based Payment Arrangement, Option [Member] Short-term borrowings and current maturities of long-term debt Debt, Current Amounts reclassified from accumulated other comprehensive loss Reclassification from Accumulated Other Comprehensive Income, Current Period, before Tax Segments [Axis] Segments [Axis] Allegion Americas Allegion 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