Employee Benefit Plans - Reconciliation of Pension Assets (Details) - Defined Benefit Pension Plans - USD ($) $ in Millions	May 31, 2025	May 31, 2024
Quoted prices in active markets (Level 1) \| Funds-of-funds
Employee benefit plans
Fair value of plan assets	$ 42.2	$ 40.7
Quoted prices in active markets (Level 1) \| Total Investments
Employee benefit plans
Fair value of plan assets	42.2	40.7
Significant other observable inputs (Level 2) \| Insurance Annuities
Employee benefit plans
Fair value of plan assets	11.4	10.7
Significant other observable inputs (Level 2) \| Total Investments
Employee benefit plans
Fair value of plan assets	11.4	10.7
Significant other unobservable inputs (Level 3) \| Funds-of-funds
Employee benefit plans
Fair value of plan assets	42.2	40.7
Significant other unobservable inputs (Level 3) \| Insurance Annuities
Employee benefit plans
Fair value of plan assets	11.4	10.7
Significant other unobservable inputs (Level 3) \| Total Investments
Employee benefit plans
Fair value of plan assets	$ 53.6	$ 51.4

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

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+ Details

AAR CORP 10-K