Fair Value Measurements - Schedule of Maturities of Debt Securities (Details) - USD ($) $ in Millions	Jun. 30, 2025	Dec. 31, 2024
Cost
After 5 years through 10 years	$ 12.1
Total debt securities	12.1	$ 12.1
Fair Value
After 5 years through 10 years	12.3
Total debt securities	$ 12.3	$ 12.3

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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TENNANT CO 10-Q