Summary of Significant Accounting Policies (Policies)	12 Months Ended
Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Accounting Policies [Abstract]
Revenue Recognition	Revenue Recognition. Refer to Note 3. for disclosures regarding our revenues.
Share-based Compensation	Stock-based Compensation. Compensation expense for stock-based awards granted to employees and directors is based on the fair value at the grant dates for our stock-settled share awards and is based on the fair value at each reporting date for our cash-settled share awards. Stock-based compensation expense is included within Selling, general and administrative expense within our consolidated statements of operations. Refer to Note 10. for more information regarding our stock-based compensation.
Cash and Cash Equivalents	Cash and Cash Equivalents. All highly liquid investments with maturities of 90 days or less when purchased are classified as cash equivalents. Where there is no right of offset against cash balances, outstanding checks are included in Accounts payable.
Receivables	Receivables, net. Receivables are amounts due from customers. To reduce credit risk, credit investigations are generally performed prior to accepting orders from new customers and, when necessary, we require letters of credit, bonds or other instruments to ensure payment. We present trade receivables net of customer discounts and an allowance for credit losses. Our consolidated statements of operations reflect the measurement of credit losses for newly recognized trade receivables, as well as the expected increases or decreases of expected credit losses that have taken place during the period. When we determine a specific trade receivable will not be collected, we charge off the uncollectible amount against the allowance. Our periodic evaluations of expected credit losses are based upon our judgments regarding prior collection experience, specific customer creditworthiness, other current conditions, and forecasts of current economic trends within the industries served that may affect the collectability of the reported amounts. Significantly weaker than anticipated industry or economic conditions could impact our customers’ ability to pay such that actual credit losses may be greater than the amounts provided for in this allowance.
Inventory Supplies, Policy		Maintenance and repair supplies and tooling. Maintenance and repair supplies and tooling is included in Other current assets and Other noncurrent assets. Costs for perishable tools and maintenance items are expensed when put into service. Costs for more durable items are amortized over their estimated useful lives, ranging from 3 to 10 years.
Inventories		Inventories, net. Inventories are recorded at the lower of first-in, first-out method cost or estimated net realizable value. We evaluate our inventory in terms of excess and obsolete exposures. This evaluation includes such factors as anticipated usage, inventory turnover, inventory levels and ultimate product sales value. Inventory cost includes an overhead component that is affected by levels of production and actual costs incurred. We periodically evaluate the effects of production levels and costs capitalized as part of Inventories, net.
Property, Plant and Equipment	Property, Plant and Equipment, net. Property, plant and equipment is recorded at cost, less accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets. Estimated useful lives are 10 to 20 years for land improvements, 10 to 40 years for buildings and 3 to 20 years for machinery and equipment. Leasehold improvements and capitalized leases are depreciated using the straight-line method over the lesser of the useful life of the asset or the remaining lease term. Gains and losses upon disposition are reflected in operating results in the period of disposition. Direct internal and external costs to implement computer systems and software for internal use are capitalized. Capitalized costs are depreciated over the estimated useful life of the system or software, generally six years, beginning when the system or software is ready for its intended use. Liabilities are recognized at fair value for asset retirement obligations related to plant and landfill closures in the period in which they are reasonably estimable and the carrying amounts of the related long-lived assets are correspondingly adjusted. Over time, the liabilities are accreted to their estimated future values. At September 30, 2023 and 2022, asset retirement obligations were $4.2 million.
Accounting for the Impairment of Long-Lived Assets	Accounting for the Impairment of Long-Lived Assets. We test indefinite-lived intangible assets and goodwill for impairment annually or more frequently if events or circumstances indicate impairment is possible. We perform our annual impairment testing at September 1. We amortize finite-lived intangible assets over their respective estimated useful lives and review for impairment if events or circumstances indicate impairment is possible. Refer to Note 5. for information regarding our goodwill impairment testing.
Workers Compensation	Workers’ Compensation. Our exposure to workers’ compensation claims is generally limited to $0.8 million per incident. Liabilities, including those related to claims incurred but not reported, are recorded principally using annual valuations based on discounted future expected payments and using historical data combined with insurance industry data when historical data is limited. Our gross workers’ compensation liabilities were $9.9 million as of September 30, 2023, and we expect to recover $4.6 million in insurance which is included as a receivable in Other current assets and Other noncurrent assets. As of September 30, 2022, our gross worker’s compensation liability was $11.1 million and our insurance receivable was $5.9 million.
Warranty Costs			Warranty Costs. We accrue for warranty expenses, which include costs to repair and/or replace, including labor, materials, equipment, freight and reasonable overhead costs. We accrue for the estimated cost of product warranties at the time of sale if such costs are determined to be probable and reasonably estimable at that time. We monitor and analyze our warranty experience and costs periodically and revise our warranty accruals as necessary. Factors considered in our accrual analyses include warranty terms, specific claim situations, general incurred and projected failure rates, the nature of product failures, product and labor costs, and general business conditions.
Deferred Financing Fees	Deferred Financing Costs. Costs to obtain debt are deferred and charged to expense over the life of the underlying debt agreement. Remaining costs and the future period over which financing costs would be charged to expense are reassessed when amendments to the related financing agreements or prepayments occur. Deferred financing costs are offset against the underlying long-term debt in the accompanying consolidated balance sheets. Deferred financing costs under agreements that do not have outstanding debt and in other instances, such as our ABL and with regard to our NMTC transaction, are included in Other noncurrent assets consistent with the life of the instrument. Deferred financing costs of $4.6 million at September 30, 2023 include: $0.5 million related to the ABL, $0.2 million related to the NMTC transaction which are amortized on a straight-line basis and; $3.9 million related to the 4.0% Senior Unsecured Notes (“4.0% Senior Notes”) which is amortized using the effective interest rate method. These amounts are amortized over the remaining term of the respective debt. Refer to Note 7. for disclosures related to our borrowing arrangements.
Income Taxes	Income Taxes. Deferred tax liabilities and deferred tax assets are recognized for the expected future tax consequences of events that have been included in the financial statements or tax returns. Such assets and liabilities are determined based on the differences between the financial statement basis and the tax basis of assets and liabilities, using tax rates in effect for the years in which the differences are expected to reverse. A valuation allowance is provided when, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized. We only record tax benefits for positions that management believes are more likely than not of being sustained under audit based solely on the technical merits of the associated tax position. The amount of tax benefit recognized for any position that meets the more-likely-than-not threshold is the largest amount of the tax benefit that we believe is greater than 50% likely of being realized.
Environmental Expenditures	Environmental Expenditures. We capitalize environmental expenditures that increase the life or efficiency of noncurrent assets or that reduce or prevent environmental contamination. We accrue for environmental expenses resulting from existing conditions that relate to past operations when the costs are probable and reasonably estimable. We are indemnified for certain environmental liabilities under an agreement with a predecessor to Tyco that existed at August 16, 1999. Refer to Note 15. for additional disclosures regarding our environmental liabilities.
Research and Development	Research and Development. Research and development costs are expensed as incurred.
Advertising	Advertising. Advertising costs are expensed as incurred.
Translation of Foreign Currency	Translation of Foreign Currency. Foreign reporting entities are remeasured into local currencies with the effect reflected in the consolidated statements of operations. Assets and liabilities of our businesses whose functional currencies are not denominated in the United States dollar are translated into United States dollars using currency exchange rates at the balance sheet date. Revenues and expenses are translated at average currency exchange rates during the period. Foreign currency translation gains and losses are reported as a component of accumulated other comprehensive income (loss). Gains and losses resulting from foreign currency transactions are included in earnings as incurred.
Recently Adopted Accounting Pronouncements and Accounting Pronouncements Not Yet Adopted	Recently Adopted Accounting Pronouncements In December 2019, the FASB issued Accounting Standards Update (“ASU”) No. 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 simplifies the accounting for income taxes by clarifying and amending existing guidance related to the recognition of franchise tax, the evaluation of a step up in the tax basis of goodwill, and the effects of enacted changes in tax laws or rates in the effective tax rate computation, among other clarifications. ASU 2019-12 is effective for public business entities for fiscal years beginning after December 15, 2020, including interim periods within that fiscal year, with early adoption permitted. We adopted this standard on October 1, 2021 and there was no material impact to our financial statements. In March 2020, the FASB issued ASU No. 2020-04, "Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting" (“ASU 2020-04”). ASU 2020-04 provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts and hedging relationships that reference the London Inter Bank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued due to reference rate reform. ASU 2020-04 is effective from March 12, 2020; however, the standard may be adopted prospectively from a date within an interim period subsequent to March 12, 2020. We adopted this standard on October 1, 2021, and there was no material impact to our financial statements. Accounting Pronouncements Not Yet Adopted In June 2022, the FASB issued ASU No. 2022-03 “Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions” (“ASU 2022-03”). ASU 2022-03 was issued to (1) clarify the guidance in Topic 820 on the fair value measurement of an equity security that is subject to a contractual sale restriction; and (2) to require specific disclosures related to such an equity security. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. We do not expect ASC 2022-03 to have a material impact on our financial statements and related disclosures. In November 2023, the FASB issued ASU No. 2023-07 “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”). ASU 2023-07 requires public business entities that disclose information on their reportable segments to provide additional information on their significant expense categories and “other segment items,” which represent the difference between segment revenue less significant segment expense and a segment’s measure of profit or loss. A description of “other segment items” is also required. Further, certain segment related disclosures that were limited to annual disclosure are now required at interim periods. Finally, public business entities are required to disclose the title and position of their Chief Operating Decision Maker (“CODM”) and explain how the CODM uses the reported measures of profit or loss to assess segment performance. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We do not expect ASU 2023-07 to have a material impact on our financial statement and related disclosures.

Summary of Significant Accounting Policies (Policies)

12 Months Ended

Sep. 30, 2023

Sep. 30, 2022

Sep. 30, 2021

Revenue Recognition. Refer to Note 3. for disclosures regarding our revenues.

Stock-based Compensation. Compensation expense for stock-based awards granted to employees and directors is based on the fair value at the grant dates for our stock-settled share awards and is based on the fair value at each reporting date for our cash-settled share awards. Stock-based compensation expense is included within Selling, general and administrative expense within our consolidated statements of operations. Refer to Note 10. for more information regarding our stock-based compensation.

Cash and Cash Equivalents

Cash and Cash Equivalents. All highly liquid investments with maturities of 90 days or less when purchased are classified as cash equivalents. Where there is no right of offset against cash balances, outstanding checks are included in Accounts payable.

Receivables

Receivables, net. Receivables are amounts due from customers. To reduce credit risk, credit investigations are generally performed prior to accepting orders from new customers and, when necessary, we require letters of credit, bonds or other instruments to ensure payment.

We present trade receivables net of customer discounts and an allowance for credit losses. Our consolidated statements of operations reflect the measurement of credit losses for newly recognized trade receivables, as well as the expected increases or decreases of expected credit losses that have taken place during the period. When we determine a specific trade receivable will not be collected, we charge off the uncollectible amount against the allowance. Our periodic evaluations of expected credit losses are based upon our judgments regarding prior collection experience, specific customer creditworthiness, other current conditions, and forecasts of current economic trends within the industries served that may affect the collectability of the reported amounts. Significantly weaker than anticipated industry or economic conditions could impact our customers’ ability to pay such that actual credit losses may be greater than the amounts provided for in this allowance.

Inventory Supplies, Policy

Maintenance and repair supplies and tooling. Maintenance and repair supplies and tooling is included in Other current assets and Other noncurrent assets. Costs for perishable tools and maintenance items are expensed when put into service. Costs for more durable items are amortized over their estimated useful lives, ranging from 3 to 10 years.

Inventories

Inventories, net. Inventories are recorded at the lower of first-in, first-out method cost or estimated net realizable value. We evaluate our inventory in terms of excess and obsolete exposures. This evaluation includes such factors as anticipated usage, inventory turnover, inventory levels and ultimate product sales value. Inventory cost includes an overhead component that is affected by levels of production and actual costs incurred. We periodically evaluate the effects of production levels and costs capitalized as part of Inventories, net.

Property, Plant and Equipment

Property, Plant and Equipment, net. Property, plant and equipment is recorded at cost, less accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets. Estimated useful lives are 10 to 20 years for land improvements, 10 to 40 years for buildings and 3 to 20 years for machinery and equipment. Leasehold improvements and capitalized leases are depreciated using the straight-line method over the lesser of the useful life of the asset or the remaining lease term. Gains and losses upon disposition are reflected in operating results in the period of disposition.

Direct internal and external costs to implement computer systems and software for internal use are capitalized. Capitalized costs are depreciated over the estimated useful life of the system or software, generally six years, beginning when the system or software is ready for its intended use.

Liabilities are recognized at fair value for asset retirement obligations related to plant and landfill closures in the period in which they are reasonably estimable and the carrying amounts of the related long-lived assets are correspondingly adjusted. Over time, the liabilities are accreted to their estimated future values. At September 30, 2023 and 2022, asset retirement obligations were $4.2 million.

Accounting for the Impairment of Long-Lived Assets

Accounting for the Impairment of Long-Lived Assets. We test indefinite-lived intangible assets and goodwill for impairment annually or more frequently if events or circumstances indicate impairment is possible. We perform our annual impairment testing at September 1. We amortize finite-lived intangible assets over their respective estimated useful lives and review for impairment if events or circumstances indicate impairment is possible. Refer to Note 5. for information regarding our goodwill impairment testing.

Workers Compensation

Workers’ Compensation. Our exposure to workers’ compensation claims is generally limited to $0.8 million per incident. Liabilities, including those related to claims incurred but not reported, are recorded principally using annual valuations based on discounted future expected payments and using historical data combined with insurance industry data when historical data is limited. Our gross workers’ compensation liabilities were $9.9 million as of September 30, 2023, and we expect to recover $4.6 million in insurance which is included as a receivable in Other current assets and Other noncurrent assets. As of September 30, 2022, our gross worker’s compensation liability was $11.1 million and our insurance receivable was $5.9 million.

Warranty Costs

Warranty Costs. We accrue for warranty expenses, which include costs to repair and/or replace, including labor, materials, equipment, freight and reasonable overhead costs. We accrue for the estimated cost of product warranties at the time of sale if such costs are determined to be probable and reasonably estimable at that time. We monitor and analyze our warranty experience and costs periodically and revise our warranty accruals as necessary. Factors considered in our accrual analyses include warranty terms, specific claim situations, general incurred and projected failure rates, the nature of product failures, product and labor costs, and general business conditions.

Deferred Financing Fees

Deferred Financing Costs. Costs to obtain debt are deferred and charged to expense over the life of the underlying debt agreement. Remaining costs and the future period over which financing costs would be charged to expense are reassessed when amendments to the related financing agreements or prepayments occur.

Deferred financing costs are offset against the underlying long-term debt in the accompanying consolidated balance sheets. Deferred financing costs under agreements that do not have outstanding debt and in other instances, such as our ABL and with regard to our NMTC transaction, are included in Other noncurrent assets consistent with the life of the instrument. Deferred financing costs of $4.6 million at September 30, 2023 include: $0.5 million related to the ABL, $0.2 million related to the NMTC transaction which are amortized on a straight-line basis and; $3.9 million related to the 4.0% Senior Unsecured Notes (“4.0% Senior Notes”) which is amortized using the effective interest rate method. These amounts are amortized over the remaining term of the respective debt. Refer to Note 7. for disclosures related to our borrowing arrangements.

Income Taxes

Income Taxes. Deferred tax liabilities and deferred tax assets are recognized for the expected future tax consequences of events that have been included in the financial statements or tax returns. Such assets and liabilities are determined based on the differences between the financial statement basis and the tax basis of assets and liabilities, using tax rates in effect for the years in which the differences are expected to reverse. A valuation allowance is provided when, based upon the available evidence, it is more likely than not that some or all of the deferred tax assets will not be realized.

We only record tax benefits for positions that management believes are more likely than not of being sustained under audit based solely on the technical merits of the associated tax position. The amount of tax benefit recognized for any position that meets the more-likely-than-not threshold is the largest amount of the tax benefit that we believe is greater than 50% likely of being realized.

Environmental Expenditures

Environmental Expenditures. We capitalize environmental expenditures that increase the life or efficiency of noncurrent assets or that reduce or prevent environmental contamination. We accrue for environmental expenses resulting from existing conditions that relate to past operations when the costs are probable and reasonably estimable. We are indemnified for certain environmental liabilities under an agreement with a predecessor to Tyco that existed at August 16, 1999. Refer to Note 15. for additional disclosures regarding our environmental liabilities.

Research and Development

Research and Development. Research and development costs are expensed as incurred.

Advertising

Advertising. Advertising costs are expensed as incurred.

Translation of Foreign Currency

Translation of Foreign Currency. Foreign reporting entities are remeasured into local currencies with the effect reflected in the consolidated statements of operations. Assets and liabilities of our businesses whose functional currencies are not denominated in the United States dollar are translated into United States dollars using currency exchange rates at the balance sheet date. Revenues and expenses are translated at average currency exchange rates during the period. Foreign currency translation gains and losses are reported as a component of accumulated other comprehensive income (loss). Gains and losses resulting from foreign currency transactions are included in earnings as incurred.

Recently Adopted Accounting Pronouncements and Accounting Pronouncements Not Yet Adopted

Recently Adopted Accounting Pronouncements

In December 2019, the FASB issued Accounting Standards Update (“ASU”) No. 2019-12, "Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes” (“ASU 2019-12”). ASU 2019-12 simplifies the accounting for income taxes by clarifying and amending existing guidance related to the recognition of franchise tax, the evaluation of a step up in the tax basis of goodwill, and the effects of enacted changes in tax laws or rates in the effective tax rate computation, among other clarifications. ASU 2019-12 is effective for public business entities for fiscal years beginning after December 15, 2020, including interim periods within that fiscal year, with early adoption permitted. We adopted this standard on October 1, 2021 and there was no material impact to our financial statements.

In March 2020, the FASB issued ASU No. 2020-04, "Reference Rate Reform (Topic 848): Facilitation of the Effects of Reference Rate Reform on Financial Reporting" (“ASU 2020-04”). ASU 2020-04 provides optional expedients and exceptions for applying GAAP to contracts, hedging relationships and other transactions affected by reference rate reform if certain criteria are met. The amendments apply only to contracts and hedging relationships that reference the London Inter Bank Offered Rate (“LIBOR”) or another reference rate expected to be discontinued due to reference rate reform. ASU 2020-04 is effective from March 12, 2020; however, the standard may be adopted prospectively from a date within an interim period subsequent to March 12, 2020. We adopted this standard on October 1, 2021, and there was no material impact to our financial statements.

Accounting Pronouncements Not Yet Adopted

In June 2022, the FASB issued ASU No. 2022-03 “Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions” (“ASU 2022-03”). ASU 2022-03 was issued to (1) clarify the guidance in Topic 820 on the fair value measurement of an equity security that is subject to a contractual sale restriction; and (2) to require specific disclosures related to such an equity security. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within those fiscal years, with early adoption permitted. We do not expect ASC 2022-03 to have a material impact on our financial statements and related disclosures.

In November 2023, the FASB issued ASU No. 2023-07 “Segment Reporting (Topic 280): Improvements to Reportable Segment Disclosures (“ASU 2023-07”). ASU 2023-07 requires public business entities that disclose information on their reportable segments to provide additional information on their significant expense categories and “other segment items,” which represent the difference between segment revenue less significant segment expense and a segment’s measure of profit or loss. A description of “other segment items” is also required. Further, certain segment related disclosures that were limited to annual disclosure are now required at interim periods. Finally, public business entities are required to disclose the title and position of their Chief Operating Decision Maker (“CODM”) and explain how the CODM uses the reported measures of profit or loss to assess segment performance. This guidance is effective for fiscal years beginning after December 15, 2023, and interim periods within fiscal years beginning after December 15, 2024. We do not expect ASU 2023-07 to have a material impact on our financial statement and related disclosures.