Summary of Significant Accounting Policies	6 Months Ended
Jun. 30, 2025
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Organization and Description of the Business Federal Signal Corporation was founded in 1901 and was reincorporated as a Delaware corporation in 1969. References herein to the “Company,” “we,” “our,” or “us” refer collectively to Federal Signal Corporation and its subsidiaries. Products manufactured and services rendered by the Company are divided into two reportable segments: Environmental Solutions Group and Safety and Security Systems Group. The individual operating businesses are organized as such because they share certain characteristics, including technology, marketing, distribution and product application, which create long-term synergies. These segments are discussed in Note 12 – Segment Information. Basis of Presentation and Consolidation The accompanying unaudited condensed consolidated financial statements represent the consolidation of Federal Signal Corporation and its subsidiaries included herein and have been prepared by the Company pursuant to the rules and regulations of the United States (“U.S.”) Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been condensed or omitted pursuant to such rules and regulations, although the Company believes that the disclosures presented herein are adequate to ensure the information presented is not misleading. Except as otherwise noted, these condensed consolidated financial statements have been prepared in accordance with the Company’s accounting policies described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, and should be read in conjunction with those consolidated financial statements and the notes thereto. These condensed consolidated financial statements include all normal and recurring adjustments that we considered necessary to present a fair statement of our results of operations, financial condition, and cash flow. Intercompany balances and transactions have been eliminated in consolidation. The results reported in these condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for the entire year, which may differ materially due to, among other things, the risk factors described under Part I, Item 1A, Risk Factors, of the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on February 26, 2025. While we label our quarterly information using a calendar convention whereby our first, second, and third quarters are labeled as ending on March 31, June 30, and September 30, respectively, it is our longstanding practice to establish interim quarterly closing dates based on a 13-week period ending on a Saturday, with our fiscal year ending on December 31. The effects of this practice are not material and exist only within a reporting year. Recent Accounting Standard Adoptions In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which expands annual and interim disclosure requirements for reportable segments, including enhanced disclosures regarding significant segment expenses. ASU 2023-07 was effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company adopted this ASU effective for the fiscal year ended December 31, 2024, and has included the required interim disclosures for all periods presented in Note 12 - Segment Information. Recent Accounting Pronouncements In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topics 740): Improvements to Income Tax Disclosures, which expands the disclosure requirements for income taxes. ASU 2023-09 is effective prospectively for annual periods beginning after December 15, 2024, with early adoption and retrospective application permitted. The Company is currently evaluating the impact of adopting this guidance on its financial statement disclosures. In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40), which requires entities to disclose, on an annual and interim basis, disaggregated information about certain income statement expense line items. ASU 2024-03 is effective prospectively for annual periods beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15, 2027, with early adoption and retrospective adoption permitted. The Company is currently evaluating the impact of adopting this guidance on its financial statement disclosures. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect (i) the reported amounts of assets and liabilities, (ii) the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and (iii) the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant Accounting Policies There have been no changes to the Company’s significant accounting policies as disclosed in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024.

Federal Signal Corporation was founded in 1901 and was reincorporated as a Delaware corporation in 1969. References herein to the “Company,” “we,” “our,” or “us” refer collectively to Federal Signal Corporation and its subsidiaries.

Products manufactured and services rendered by the Company are divided into two reportable segments: Environmental Solutions Group and Safety and Security Systems Group. The individual operating businesses are organized as such because they share certain characteristics, including technology, marketing, distribution and product application, which create long-term synergies. These segments are discussed in Note 12 – Segment Information.

The accompanying unaudited condensed consolidated financial statements represent the consolidation of Federal Signal Corporation and its subsidiaries included herein and have been prepared by the Company pursuant to the rules and regulations of the United States (“U.S.”) Securities and Exchange Commission (the “SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with U.S. generally accepted accounting principles (“GAAP”) have been condensed or omitted pursuant to such rules and regulations, although the Company believes that the disclosures presented herein are adequate to ensure the information presented is not misleading. Except as otherwise noted, these condensed consolidated financial statements have been prepared in accordance with the Company’s accounting policies described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, and should be read in conjunction with those consolidated financial statements and the notes thereto.

These condensed consolidated financial statements include all normal and recurring adjustments that we considered necessary to present a fair statement of our results of operations, financial condition, and cash flow. Intercompany balances and transactions have been eliminated in consolidation.

The results reported in these condensed consolidated financial statements should not be regarded as necessarily indicative of results that may be expected for the entire year, which may differ materially due to, among other things, the risk factors described under Part I, Item 1A, Risk Factors, of the Company’s Annual Report on Form 10-K for the year ended December 31, 2024, which was filed with the SEC on February 26, 2025. While we label our quarterly information using a calendar convention whereby our first, second, and third quarters are labeled as ending on March 31, June 30, and September 30, respectively, it is our longstanding practice to establish interim quarterly closing dates based on a 13-week period ending on a Saturday, with our fiscal year ending on December 31. The effects of this practice are not material and exist only within a reporting year.

In November 2023, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2023-07, Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures, which expands annual and interim disclosure requirements for reportable segments, including enhanced disclosures regarding significant segment expenses. ASU 2023-07 was effective for fiscal years beginning after December 15, 2023, and for interim periods within fiscal years beginning after December 15, 2024, with early adoption permitted. The Company adopted this ASU effective for the fiscal year ended December 31, 2024, and has included the required interim disclosures for all periods presented in Note 12 - Segment Information.

In December 2023, the FASB issued ASU 2023-09, Income Taxes (Topics 740): Improvements to Income Tax Disclosures, which expands the disclosure requirements for income taxes. ASU 2023-09 is effective prospectively for annual periods beginning after December 15, 2024, with early adoption and retrospective application permitted. The Company is currently evaluating the impact of adopting this guidance on its financial statement disclosures.

In November 2024, the FASB issued ASU 2024-03, Income Statement - Reporting Comprehensive Income-Expense Disaggregation Disclosures (Subtopic 220-40), which requires entities to disclose, on an annual and interim basis, disaggregated information about certain income statement expense line items. ASU 2024-03 is effective prospectively for annual periods beginning after December 15, 2026, and for interim periods within fiscal years beginning after December 15,

The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect (i) the reported amounts of assets and liabilities, (ii) the disclosure of contingent assets and liabilities at the date of the condensed consolidated financial statements, and (iii) the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.