Income Taxes - Income (Loss) from Continuing Operations before Taxes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Income Tax Disclosure [Abstract]
Income (Loss) from Continuing Operations before Income Taxes, Domestic	$ 288.8	$ 234.5	$ 176.6
Income (Loss) from Continuing Operations before Income Taxes, Foreign	35.7	29.4	26.4
Income before income taxes	$ 324.5	$ 263.9	$ 203.0

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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FEDERAL SIGNAL CORP /DE/ 10-K