Funds Held for Clients and Corporate Investments (Classification of Investments on Consolidated Balance Sheets) (Details) - USD ($) $ in Millions |
May 31, 2026 |
May 31, 2025 |
|---|---|---|
| Funds Held for Clients and Corporate Investments [Abstract] | ||
| Funds held for clients | $ 4,832.2 | $ 4,813.3 |
| Corporate investments | 36.3 | 34.5 |
| Total funds held for clients and corporate investments, Fair value | $ 4,868.5 | $ 4,847.8 |