Mueller Water Products (MWA) 10-K 18 Nov 22 2022 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Nov. 10, 2022	Mar. 31, 2022	Sep. 30, 2021
Document Information [Line Items]
Document Fiscal Period Focus	FY
Document Period End Date	Sep. 30, 2022
Document Fiscal Year Focus	2022
Entity Well-known Seasoned Issuer	Yes
Entity Registrant Name	MUELLER WATER PRODUCTS, INC.
Entity Central Index Key	0001350593
Current Fiscal Year End Date	--09-30
Entity Filer Category	Large Accelerated Filer
Document Type	10-K
Property, plant and equipment, net	$ 301.6			$ 283.4
Intangible Assets, Net (Including Goodwill)	$ 459.8			$ 507.6
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Amendment Flag	false
Entity Common Stock, Shares Outstanding		155,891,768
Entity Shell Company	false
Entity Emerging Growth Company	false
Entity Small Business	false
Entity Public Float			$ 2,001.3
ICFR Auditor Attestation Flag	true

Cover Page Document

Cover Page Document	12 Months Ended
	Sep. 30, 2022
Cover Page [Abstract]
Document Type	10-K
Documents Incorporated by Reference [Text Block]	Applicable portions of the Proxy Statement for the upcoming 2023 Annual Meeting of Stockholders of the Company are incorporated by reference into Part III of this Form 10-K.
Title of 12(b) Security	Common Stock, par value $0.01
Entity Address, Address Line Two	Suite 1200
Entity Incorporation, State or Country Code	DE
Document Transition Report	false
Document Annual Report	true
Document Period End Date	Sep. 30, 2022
Entity File Number	001-32892
Entity Registrant Name	MUELLER WATER PRODUCTS, INC.
Entity Tax Identification Number	20-3547095
Entity Address, Address Line One	1200 Abernathy Road N.E.
Entity Address, City or Town	Atlanta
Entity Address, State or Province	GA
Entity Address, Postal Zip Code	30328
City Area Code	(770)
Local Phone Number	206-4200
Trading Symbol	MWA
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false

Cover

Cover	12 Months Ended
	Sep. 30, 2022
Cover [Abstract]
Documents Incorporated by Reference [Text Block]	Applicable portions of the Proxy Statement for the upcoming 2023 Annual Meeting of Stockholders of the Company are incorporated by reference into Part III of this Form 10-K.

Audit Information

Audit Information	12 Months Ended
	Sep. 30, 2022
Auditor [Line Items]
Auditor Name	Ernst & Young LLP
Auditor Firm ID	42
Auditor Location	Atlanta, Georgia

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Assets:
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 146.5	$ 227.5
Receivables, net	228	212.2
Inventories	278.7	184.7
Other current assets	26.8	29.3
Total current assets	680	653.7
Property, plant and equipment, net	301.6	283.4
Intangible Assets, Net (Excluding Goodwill)	361.2	392.5
Goodwill	98.6	115.1
Other noncurrent assets	56.7	73.3
Total assets	1,498.1	1,518
Liabilities and equity:
Current portion of long-term debt	0.8	1
Accounts payable	122.8	92
Other current liabilities	117.4	127.1
Liabilities, Current	241	220.1
Long-term debt, excluding current maturities	446.1	445.9
Deferred Tax Liabilities, Gross, Noncurrent	86.3	95.1
Other noncurrent liabilities	55.4	62
Total liabilities	828.8	823.1
Common Stock	1.6	1.6
Additional paid-in capital	1,279.6	1,342.2
Accumulated deficit	(567.3)	(643.9)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(44.6)	(5)
Stockholders' Equity Attributable to Parent	669.3	694.9
Equity		694.9
Total liabilities and equity	1,498.1	1,518
Accounts Receivable, Allowance for Credit Loss, Current	$ 5.6	$ 3.5

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical)	Sep. 30, 2022 shares
Statement of Financial Position [Abstract]
Series A common stock, shares authorized	600,000,000
Series A common stock, shares outstanding	155,844,138

Consolidated Statements Of Oper

Consolidated Statements Of Operations - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenues	$ 1,247.4	$ 1,111	$ 964.1
Cost of sales	883.1	752.5	635.9
Gross profit	364.3	358.5	328.2
Operating expenses:
Selling, general and administrative	238.7	218.8	198.4
Other Cost and Expense, Operating	7.2	8	13
Goodwill, Impairment Loss	6.8	0	0
Total operating expenses	252.7	226.8	211.4
Operating income	111.6	131.7	116.8
Defined Benefit Plan, Net Periodic Benefit Cost other than Service Cost	(3.9)	(3.3)	(3)
Interest expense, net	16.9	23.4	25.5
Walter Energy Accrual	0	0	0.2
Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest	98.6	94.9	94.1
Loss on early extinguishment of debt	0	16.7	0
Income tax expense (benefit)	22	24.5	22.1
Net Income (Loss) Attributable to Parent	$ 76.6	$ 70.4	$ 72
Net loss per basic share:
Continuing operations, in dollars per share	$ 0.49	$ 0.44	$ 0.46
Net loss per diluted share:
Continuing operations	$ 0.48	$ 0.44	$ 0.45
Weighted average shares outstanding:
Basic, in shares	157.4	158.4	157.8
Diluted, in shares	158	159.2	158.6
Dividends declared per share, in dollars per share	$ 0.232	$ 0.22	$ 0.21

Consolidated Statement of Compr

Consolidated Statement of Comprehensive Income Statement - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Net Income (Loss) Attributable to Parent	$ 76.6	$ 70.4	$ 72
Other comprehensive income (loss):
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	18.8	(14.1)	(4.4)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	4.7	(3.6)	(1.1)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	(25.5)	9.2	8
Other Comprehensive Income (Loss), Net of Tax	(39.6)	19.7	11.3
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 37	$ 90.1	$ 83.3

Consolidated Statement Of Stock

Consolidated Statement Of Stockholders' Equity - USD ($) $ in Millions	Total	Common stock	Additional paid-in capital	Accumulated deficit	Accumulated other comprehensive income (loss)	Noncontrolling Interest [Member]	Stock-based Compensation Related [Member]	Stock-based Compensation Related [Member] Common stock	Stock-based Compensation Related [Member] Additional paid-in capital	Stock-based Compensation Related [Member] Accumulated deficit	Stock-based Compensation Related [Member] Accumulated other comprehensive income (loss)	Stock-based Compensation Related [Member] Noncontrolling Interest [Member]
Balance at Sep. 30, 2019	$ 592.3	$ 1.6	$ 1,410.7	$ (786.2)	$ (36)	$ 2.2
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	72
Net Income (Loss) Attributable to Noncontrolling Interest						0
Net Income (Loss) Attributable to Parent	72	0	0	72	0
Dividends declared	(33.1)	0	(33.1)	0	0	0
Stock-based compensation	5.3	0	5.3	0	0	0
Shares retained for employee taxes							$ (0.9)	$ 0	$ (0.9)	$ 0	$ 0	$ 0
Stock issued under stock compensation plans	3.5	0	3.5	0	0	0
Stock repurchased under buyback program	(5)	0	(5)	0	0	0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(4.7)	0	2.5	0	0	2.2
Other Comprehensive Income (Loss), Net of Tax	11.3	0	0	0	11.3	0
Balance at Sep. 30, 2020	640.7	1.6	1,378	(714.2)	(24.7)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	70.4
Net Income (Loss) Attributable to Noncontrolling Interest						0
Net Income (Loss) Attributable to Parent	70.4	0	0	70.4	0
Dividends declared	(34.8)	0	(34.8)	0	0	0
Stock-based compensation	8.1	0	8.1	0	0	0
Shares retained for employee taxes							(1)	0	$ (1)	0	0	0
Stock issued under stock compensation plans	1.9	0	1.9	0	0	0
Stock repurchased under buyback program	(10)	0	(10)	0	0	0
Other Comprehensive Income (Loss), Net of Tax	19.7	0	0	0	19.7	0
Balance at Sep. 30, 2021	694.9	1.6	1,342.2	(643.9)	(5)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Cumulative Effect of Accounting Change	(0.1)	0	0	(0.1)	0	0
Stockholders' Equity Attributable to Parent	694.9
Net income (loss)	76.6
Net Income (Loss) Attributable to Noncontrolling Interest						0
Net Income (Loss) Attributable to Parent	76.6	0	0		0
Dividends declared	(36.5)	0	(36.5)	0	0	0
Stock-based compensation	8.7	0	8.7	0	0	0
Shares retained for employee taxes							$ (1.8)	$ 0		$ 0	$ 0	$ 0
Stock issued under stock compensation plans	2	0	2	0	0	0
Stock repurchased under buyback program	(35)	0	(35)	0	0	0
Other Comprehensive Income (Loss), Net of Tax	(39.6)	0	0	0	(39.6)	0
Stockholders' Equity Attributable to Parent	$ 669.3	$ 1.6	$ 1,279.6	$ (567.3)	$ (44.6)	$ 0

Consolidated Statements Of Cash

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Operating Activities
Net Income (Loss) Attributable to Parent	$ 76.6	$ 70.4	$ 72
Adjustments to reconcile net income (loss) to income (loss) from continuing operations:
Depreciation	32	31.4	29.6
Amortization	28.5	28.2	28.2
Goodwill, Impairment Loss	(6.8)	0	0
Pension plans	(2.6)	(1.9)	2.8
Deferred income taxes	(3.5)	(5.3)	7.2
Inventory disposed	1.6	3.1	4.3
Stock-based compensation expense	8.7	8.1	5.3
Loss on early extinguishment of debt	0	16.7	0
Other, net	1.3	1.3	3.7
Changes in assets and liabilities, net of acquisitions:
Receivables	(17.8)	(29.9)	(7.5)
Inventories	(98.3)	(23.5)	24.9
Other current assets and other noncurrent assets	1.3	(4.9)	0.9
Accounts payable	32.2	23	(17.6)
Walter Energy accrual	0	0	(22)
Increase (Decrease) in Accrued Liabilities	(8.5)	37.5	6.6
Long-term liabilities	(6)	2.5	1.9
Net Cash Provided by (Used in) Operating Activities, Total	52.3	156.7	140.3
Investing activities:
Capital expenditures	(54.7)	(62.7)	(67.7)
Acquisitions, net of cash acquired	0.2	19.7	0
Proceeds from sales of assets	0	0.7	0.2
Net Cash Provided by (Used in) Investing Activities, Total	(54.9)	(81.7)	(67.5)
Financing activities:
Dividends paid	(36.5)	(34.8)	(33.1)
Payments to Noncontrolling Interests	0	0	(5.2)
Payments for Repurchase of Common Stock	(35)	(10)	(5)
Common stock issued	2	1.9	3.5
Shares retained for employee taxes	(1.8)	(1)	(0.9)
Repayment of debt	0	(462.4)	0
Repayment of Krausz debt	0.7	0.4	0.4
Issuance of debt	0	450	0
Payment of deferred financing fees	0	(6)	(1.1)
Proceeds from Other Equity	0	3.9	0
Net Cash Provided by (Used in) Financing Activities, Total	(72)	(58.8)	(41.4)
Effect of Exchange Rate on Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Continuing Operations	(6.4)	2.4	0.8
Net change in cash and cash equivalents	(81)	18.6	32.2
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	146.5	227.5	208.9
Interest Paid, Excluding Capitalized Interest, Operating Activities	19.2	25.3	24.3
Income Taxes Paid	26.9	16.8	15.3
Goodwill, Gross	822.7	832.4	817.1
Goodwill, Impaired, Accumulated Impairment Loss	(724.1)	(717.3)	(717.3)
Goodwill	$ 98.6	$ 115.1	$ 99.8

Statement of Financial Position

Statement of Financial Position, Classified (Statement) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Inventory, Work in Process, Net of Reserves	$ 56.8	$ 33.5
Inventory, Finished Goods, Net of Reserves	40.1	44.6
Inventories	278.7	184.7
Prepaid Expense	14.6	12.8
Inventory, Raw Materials and Purchased Parts, Net of Reserves	181.8	106.6
Income Taxes Receivable, Current	0.8	0.2
Maintenance and repair tooling	2.8	2.9
Other Receivables	2.6	0.8
Other Prepaid Expense, Current	4.4	1.9
Other current assets	26.8	29.3
Land	5.7	6.1
Buildings and Improvements, Gross	87.6	84.6
Machinery and Equipment, Gross	456	433.3
Construction in Progress, Gross	104.7	83.7
Property, Plant and Equipment, Gross	654	607.7
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	(352.4)	(324.3)
Property, plant and equipment, net	301.6	283.4
Operating Lease, Right-of-Use Asset	26	27.1
Maintenance, repair and tooling supplies	20.4	19.3
Nontrade Receivables, Noncurrent	3.6	2.7
Notes Receivable, Related Parties, Noncurrent	1.7	1.8
Pension asset	0.6	16.8
Debt Issuance Costs, Noncurrent, Net	1	1.3
Maintenance and repair supplies and tooling, Noncurrent	3.4	4.3
Other noncurrent assets	56.7	73.3
Compensation and benefits	40.2	44.6
Accrued rebates	16.2	19.6
Interest Payable	5.3	6.2
Standard and Extended Product Warranty Accrual	6.5	6.7
Deferred revenues	8.1	5.4
Customer refund liability	4.2	6
Operating lease liability	4.4	4
Accrual for Taxes Other than Income Taxes	4.4	4.4
Restructuring Reserve, Current	3.3	3.1
Environmental	0.7	1.2
Accrued Income Taxes	7.5	8.5
Workers' Compensation Liability, Current	4.6	2.6
CARES Act payroll tax liabilities, current	4.4	3.6
Other current liabilities	7.6	11.2
Other current liabilities	117.4	127.1
Operating Lease, Liability, Noncurrent	22.4	24.6
Standard Product Warranty Accrual, Noncurrent	4.2	3
transition tax liability	4.1	4.7
Unrecognized Tax Benefits	4.7	4.8
Workers' Compensation Liability, Noncurrent	6.5	7.9
NMTC liability	3.9	3.9
Asset Retirement Obligations, Noncurrent	3.6	3.6
CARES Act payroll tax liabilities, noncurrent	0	3.6
Deferred development grant	2.5	2.5
Other Accrued Liabilities, Noncurrent	3.5	3.4
Other noncurrent liabilities	55.4	62
Nontrade Receivables, Current	$ 1.6	10.7
CaresActTotalFY21		$ 7.2

Statement of Other Comprehensiv

Statement of Other Comprehensive Income (Statement) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ (8.3)	$ 17.2
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	(36.3)	(22.2)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(44.6)	(5)
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss), before Reclassification and Tax	(25.5)
OCI, before Reclassifications, Net of Tax, Attributable to Parent	(39.6)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, before Tax	(14.1)
Other Comprehensive Income (Loss), Net of Tax	(39.6)	19.7
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	$ (25.5)	$ 9.2

Statement of Other Comprehens_2

Statement of Other Comprehensive Income	12 Months Ended
	Sep. 30, 2022
Statement of Other Comprehensive Income [Abstract]
Comprehensive Income (Loss) Note [Text Block]	Accumulated Other Comprehensive Income (Loss) Accumulated other comprehensive income (loss) is as follows: Foreign currency translation Pension liability, net of tax Total (in millions) Balance at September 30, 2021 $ 17.2 $ (22.2) $ (5.0) Current period other comprehensive income (25.5) (14.1) (39.6) Balance at September 30, 2022 $ (8.3) $ (36.3) $ (44.6)

Supplemental Balance Sheet

Supplemental Balance Sheet	12 Months Ended
	Sep. 30, 2022
Statement of Financial Position [Abstract]
Supplemental Balance Sheet - Schedules of Assets	Selected supplemental asset information is presented below. September 30, 2022 2021 (in millions) Inventories, net: Purchased components and raw materials $ 181.8 $ 106.6 Work in process 56.8 33.5 Finished goods 40.1 44.6 Total inventories, net $ 278.7 $ 184.7 Other current assets: Prepaid expenses $ 14.6 $ 12.8 Non-trade receivables 1.6 10.7 Income taxes 0.8 0.2 Maintenance and repair supplies and tooling 2.8 2.9 Workers’ compensation reimbursement receivable 2.6 0.8 Other current assets 4.4 1.9 Total other current assets $ 26.8 $ 29.3 Property, plant and equipment, net: Land $ 5.7 $ 6.1 Buildings 87.6 84.6 Machinery and equipment 456.0 433.3 Construction in progress 104.7 83.7 Total property, plant and equipment $ 654.0 $ 607.7 Accumulated depreciation (352.4) (324.3) Total property, plant and equipment, net $ 301.6 $ 283.4 Other noncurrent assets: Operating lease right-of-use assets $ 26.0 $ 27.1 Maintenance and repair supplies and tooling 20.4 19.3 Workers’ compensation reimbursement receivable 3.6 2.7 Note receivable 1.7 1.8 Pension assets 0.6 16.8 Deferred financing fees 1.0 1.3 Other noncurrent assets 3.4 4.3 Total noncurrent assets $ 56.7 $ 73.3
Supplemental Balance Sheet - Schedule of Liabilities	Selected supplemental liability information is presented below. September 30, 2022 2021 (in millions) Other current liabilities: Compensation and benefits $ 40.2 $ 44.6 Customer rebates 16.2 19.6 Interest payable 5.3 6.2 Warranty accrual 6.5 6.7 Deferred revenues 8.1 5.4 Refund liability 4.2 6.0 Operating lease liabilities 4.4 4.0 Taxes other than income taxes 4.4 4.4 Restructuring liabilities 3.3 3.1 Environmental liabilities 0.7 1.2 Income taxes payable 7.5 8.5 Workers’ compensation accrual 4.6 2.6 CARES Act payroll tax liabilities 4.4 3.6 Other current liabilities 7.6 11.2 Total current liabilities $ 117.4 $ 127.1 Other noncurrent liabilities: Operating lease liabilities $ 22.4 $ 24.6 Warranty accrual 4.2 3.0 Transition tax liability 4.1 4.7 Uncertain tax position liability 4.7 4.8 Workers' compensation accrual 6.5 7.9 NMTC liability 3.9 3.9 Asset retirement obligation 3.6 3.6 CARES Act payroll tax liabilities — 3.6 Deferred development grant 2.5 2.5 Other noncurrent liabilities 3.5 3.4 Total noncurrent liabilities $ 55.4 $ 62.0

Other Comprehensive Income (Tab

Other Comprehensive Income (Tabular)	12 Months Ended
	Sep. 30, 2022
Statement of Other Comprehensive Income [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block]	Accumulated other comprehensive income (loss) is as follows: Foreign currency translation Pension liability, net of tax Total (in millions) Balance at September 30, 2021 $ 17.2 $ (22.2) $ (5.0) Current period other comprehensive income (25.5) (14.1) (39.6) Balance at September 30, 2022 $ (8.3) $ (36.3) $ (44.6)

Summary of Significant Accounti

Summary of Significant Accounting Policies All (Notes)	12 Months Ended
	Sep. 30, 2022
Accounting Policies [Abstract]
Significant Accounting Policies [Text Block]	Summary of Significant Accounting Policies Cash and Cash Equivalents. All highly liquid investments with remaining 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, 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, letters of credit, bonds or other instruments are required 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. The following table summarizes information concerning our allowance for credit losses. 2022 2021 2020 (in millions) Balance at beginning of year $ 3.5 $ 2.5 $ 1.5 Provision charged to expense 2.5 1.1 1.1 Other (0.4) (0.1) (0.1) Balance at end of year $ 5.6 $ 3.5 $ 2.5 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 inventory. The following table summarizes information concerning our inventory valuation reserves. 2022 2021 2020 (in millions) Balance at beginning of year $ 14.8 $ 11.7 $ 7.5 Provision charged to expense 1.8 5.9 4.7 Inventory disposed (1.4) (3.6) (0.7) Other 1.3 0.8 0.2 Balance at end of year $ 16.5 $ 14.8 $ 11.7 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. 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 15 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 internal-use software are capitalized. Capitalized costs are depreciated over the estimated useful life of the system or software, generally six 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, 2022 and 2021, asset retirement obligations were $3.6 million and $3.8 million, respectively. Leases. Refer to Note 4. for information regarding our leases. 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 6. for information regarding our goodwill impairment testing. 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 $11.1 million as of September 30, 2022, and we expect to recover $5.9 million in insurance which is included as a receivable in Other current assets and Other noncurrent assets as of September 30, 2022. As of September 30, 2021, our gross worker’s compensation liability was $10.5 million and our insurance receivable was 3.5 million. Warranty Costs. We accrue for warranty expenses, which include costs of repair and/or replacement, 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. Critical factors 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. Activity in our accrued warranty, reported as part of both other current liabilities and other noncurrent liabilities, is presented below. 2022 2021 2020 (in millions) Balance at beginning of year $ 9.7 $ 14.4 $ 17.1 Warranty accruals 9.5 3.5 2.6 Warranty costs (8.5) (8.2) (5.3) Balance at end of year $ 10.7 $ 9.7 $ 14.4 Deferred Financing Costs. Debt issuance 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 N MTC transaction, are included in Other noncurrent assets consistent with the life of the instrument. Deferred financing costs of $5.6 million at September 30, 2022 are scheduled to amortize as follows: $0.7 million related to the ABL, $0.3 million related to the NMTC transaction which are amortized on a straight-line basis and; $4.6 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 8. for disclosures related to our borrowing arrangements. Derivative Instruments and Hedging Activities. We manage U.S. dollar - Canadian dollar exchange rate risk related to intercompany loans with swap contracts from time to time without designating these swap contracts as a hedge. As a result, the changes in the fair value of these contracts have been reported in earnings. As of September 30, 2021, we had a $1.1 million liability in Other current liabilities in our consolidated balance sheets related to such a hedge. These currency swap contracts expired in February 2022, and we did not have any liabilities related to currency swap contracts as of September 30, 2022. 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. 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 17. for additional disclosures regarding our environmental liabilities. 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 12. for more information regarding our stock-based compensation. Research and Development. Research and development costs are expensed as incurred. Advertising. Advertising costs are expensed as incurred. 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 During 2016, the Financial Accounting Standards Board (“FASB”) issued standard Accounting Standard Codification (“ASC”) 326 - Current Expected Credit Losses (“ASC 326”) to replace the “incurred loss” impairment approach with an “expected loss” approach. This requires consideration of a broader range of reasonable and supportable information to estimate credit losses. We have completed historical and forward-looking analyses for receivables and adopted this guidance effective October 1, 2020. Upon adoption, there was no material impact to our financial statements. 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”). The new guidance 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, can 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 ASU 2022-03 Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions: The FASB issued this update in June 2022, 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. Management does not expect that changes required by the new standard will have a material impact on our financial statements and related disclosures.

Revenue from Contracts with Cus

Revenue from Contracts with Customers Revenue from Contracts with Customers	12 Months Ended
	Sep. 30, 2022
Revenue from Contract with Customer [Abstract]
Revenue from Contract with Customer [Text Block]	Revenue from Contracts with Customers We recognize revenue when control of promised products or services is transferred to our customers, in amounts that reflect the consideration to which we expect to be entitled in exchange for those products or services. We account for a contract when it has approval and commitment from both parties, the rights of the parties are identified, the payment terms are identified, the contract has commercial substance and collectability of consideration is probable. We determine the appropriate revenue recognition for our contracts with customers by analyzing the type, terms and conditions of each contract or arrangement with a customer. Disaggregation of Revenue Refer to Note 16. for disaggregation our revenues from contracts with customers by reportable segment and by geographical region, which we believe best depicts how the nature, amount, timing and uncertainty of our revenue and cash flows are affected by economic factors. Geographical region represents the location of the customer. Contract Asset and Liability Balances Differences in the timing of revenue recognition, billing and cash collection result in customer receivables, advance payments and billings in excess of revenue recognized. Customer receivables include amounts billed and currently due from customers as well as unbilled amounts (contract assets). Amounts are billed in accordance with contractual terms and unbilled amounts arise when the timing of billing differs from the timing of revenue recognized. Advance payments and billings in excess of revenue are recognized and recorded as deferred revenue, the majority of which is classified as current based on the timing when we expect to recognize revenue. We include current deferred revenue within Other current liabilities in the accompanying consolidated balance sheets. Deferred revenues represent contract liabilities and are recorded when customers remit cash payments in advance of our satisfaction of performance obligations under contractual arrangements. Contract liabilities are reversed when the performance obligation is satisfied and revenue is recognized. The table below represents the balances of our customer receivables and deferred revenues. September 30, 2022 2021 (in millions) Billed receivables $ 230.5 $ 213.4 Unbilled receivables 3.1 2.3 Gross customer receivables $ 233.6 $ 215.7 Allowance for credit losses (5.6) (3.5) Receivables, net $ 228.0 $ 212.2 Deferred revenues $ 8.1 $ 5.4 Performance Obligations A performance obligation is a promise in a contract to transfer a distinct good or service to the customer. Our performance obligations are satisfied at a point in time as related to sales of equipment or over time as related to our software hosting and leak detection monitoring services. Performance obligations are supported by customer contracts, which provide frameworks for the nature of the distinct products or services. The transaction price is adjusted for our estimate of variable consideration which may include discounts, and rebates. To estimate variable consideration, we apply the expected value or the most likely amount method, based on whichever method most appropriately predicts the amount of consideration we expect to receive. The method applied is typically based on historical experience and known trends. We constrain the amounts of variable consideration that are included in the transaction price, to the extent that it is probable that a significant reversal in the amount of cumulative revenue recognized will not occur or when uncertainties around the variable consideration are resolved. We exclude from the measurement of the transaction price all taxes assessed by a governmental authority. We have elected to use the practical expedient to not adjust the transaction price of a contract for the effects of a significant financing component if, at the inception of the contract, we expect that the period between when we transfer a product or service to a customer and when a customer remits payment will be one year or less. Revenues from products and services transferred to customers at a point in time represente d 98% in the fiscal years 2022 and 2021, and 99% of our revenues in the fiscal year 2020. The revenues recognized at a point in time related to the sale of our products are recognized when the obligations of the terms of our contract are satisfied, which is when the customer is able to direct the use of and obtain substantially all of the benefits from the product, which generally occurs upon shipment when control of the product transfers to the customer. Revenues from products and services transferred to customers over time represented 2% of our revenues in the fiscal years 2022, and 2021, and 1% of our revenues in the fiscal year 2020. We offer warranties to our customers in the form of assurance-type warranties, which provide assurance that the products provided will function as intended and comply with any agreed-upon specifications. These cannot be purchased separately. Costs to Obtain or Fulfill a Contract Shipping and handling costs associated with freight activities after the customer has obtained control are accounted for as fulfillment costs and are expensed and accrued at the time revenue is recognized, as a component of cost of sales. We incur certain incremental costs to obtain a contract, which primarily relate to incremental sales commissions. Our commissions are paid based on a combination of orders and shipments, and we reserve the right to claw back any commissions in case of product returns or lost collections. As the expected benefit associated with these incremental costs is generally one year or less based on the nature of the product sold and benefits received, we have applied a practical expedient and therefore do not capitalize the related costs and expense them as incurred.

Business Combination Business C

Business Combination Business Combination	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Business Combination Disclosure [Text Block]	Acquisitions

Identifiable Intangible Assets

Identifiable Intangible Assets	12 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Identifiable Intangible Assets	Intangible Assets and Goodwill Goodwill is tested for impairment at the reporting unit level (operating segment or one level below an operating segment) on an annual basis each September 1 st and between annual tests if an event occurs or circumstances change that would more likely than not reduce the fair value of a reporting unit below its carrying value. We performed the annual impairment testing at September 1, 2022 and recognized a $6.8 million goodwill impairment charge related to a reporting unit within our Water Flow Solutions segment as the carrying value exceeded its fair value primarily due to an increase in the discount rate. The carrying value of the reporting unit, including goodwill, is compared with the estimated fair value of the reporting unit as determined utilizing a combination of the income and market approaches. The income approach, which involved significant unobservable inputs (Level 3 inputs), is based on projected debt-free cash flow which is discounted to the present value using discount rates that consider the timing and risk of the cash flows. The market approach is based on the guideline public company method, which uses market multiples to value our reporting units. The Company weights the income and market approaches in a manner considering the risks of the underlying cash flows. The key assumptions used in estimating the fair value of the Company's reporting units utilizing the income approach include management's best estimate of revenue, EBITDA margin, and discount rate, and accordingly, a change in market conditions or other factors could have a material effect on the estimated values. There are inherent uncertainties related to the assumptions used and to management's application of these assumptions. Intangible Assets Direct internal and external costs to develop software used in the provision of services to customers by Water Management Solutions are capitalized and amortized over the 6-year estimated useful life of the software, beginning when the software is ready for its intended use. At September 30, 2022, the remaining weighted-average amortization period for this software was 3.6 years. Amortization expense related to such software assets was $2.9 million in 2022 , and $3.3 million in each of fiscal years 2021 and 2020. Amortization expense for each of the next five years is expected to be $3.1 million in 2023, $2.5 million in 2024, $1.5 million in 2025, $0.9 million in 2026, and $0.5 million in 2027. At September 30, 2022, the remaining weighted-average amortization period for business combination-related finite-lived customer relationships and technology intangible assets wer e 3.3 years and 8.5 years, respectively. Amortization expense related to these assets was $25.5 million , $25.2 million and $24.9 million for 2022, 2021 and 2020, respectively. Amortization expense for each of the next five years is scheduled to be $25.1 million in 2023, $24.6 million in 2024, $5.6 million in 2025, $4.9 million in 2026 and $4.7 million in 2027. Intangible assets are presented below. September 30, 2022 2021 (in millions) Capitalized internal-use software: Cost $ 35.5 $ 34.1 Accumulated amortization (26.8) (24.1) Capitalized internal-use software, net $ 8.7 $ 10.0 Business combination-related: Cost: Finite-lived intangible assets: Technology 119.9 123.5 Customer relationships and other 371.6 373.0 Indefinite-lived intangible assets: Trade names and trademarks 272.7 273.8 $ 764.2 $ 770.3 Accumulated amortization: Technology (89.5) (85.8) Customer relationships and other (322.2) (302.0) (411.7) (387.8) Business combination-related intangible assets, net 352.5 382.5 Intangible assets, net $ 361.2 $ 392.5 Goodwill We recognized a $6.8 million goodwill impairment charge related to a reporting unit within our Water Flow Solutions segment in our fiscal year 2022. As of September 30, 2022, o ur remaining goodwill balance is within our Water Management Solutions segment. Changes in the carrying amount of goodwill for the years ended September 30, 2022 and 2021 were as follows:

Income Taxes

Income Taxes	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The components of income before income taxes are presented below. 2022 2021 2020 (in millions) U.S. $ 81.6 $ 94.0 $ 89.7 Non-U.S. 17.0 0.9 4.4 Income before income taxes $ 98.6 $ 94.9 $ 94.1 The Tax Cuts and Jobs Act (the “Act”) imposed a one-time transition tax on the undistributed, previously untaxed, post-1986 foreign “earnings and profits” as defined by the Internal Revenue Services (“IRS”) of certain United States-owned corporations. At September 30, 2022, the remaining balance of our transition obligation is $4.1 million , which will be paid annually through January 2026, as provided in the Act. Other than for Krausz’s investment in its United States subsidiary, we have not recorded income taxes for unrepatriated foreign earnings that may be subject to withholding tax or any outside cost basis differences inherent in our foreign subsidiaries, as these amounts continue to be indefinitely reinvested in foreign operations. We have a foreign tax credit carryforward of $4.5 million , for which we have recorded a valuation allowance as we do not expect to utilize it prior to expiration. The federal income tax returns for Mueller Water Products, Inc. are closed for years prior to 2018. We remain liable for any taxes related to U.S. Pipe income for periods prior to 2012 pursuant to the terms of the sale agreement with the purchaser of the segment. Our state income tax returns are generally closed for years prior to 2018, except with regard to our state net operating loss carryforwards. Our Canadian income tax returns are generally closed for years prior to 2015. We do not have any material unpaid assessments . The components of income tax expense are as follows: 2022 2021 2020 (in millions) Current: U.S. federal $ 19.5 $ 21.9 $ 10.9 U.S. state and local 4.3 6.3 2.7 Non-U.S. 1.7 1.6 1.3 Total current income tax expense 25.5 29.8 14.9 Deferred: U.S. federal (3.4) (4.7) 5.6 U.S. state and local (0.9) (1.3) 2.0 Non-U.S. 0.8 0.7 (0.4) Total deferred income tax (benefit) expense (3.5) (5.3) 7.2 Income tax expense $ 22.0 $ 24.5 $ 22.1 The reconciliation between income tax expense at the United States federal statutory income tax rate and reported income tax expense is presented below. 2022 2021 2020 (in millions) Expense at U.S. federal statutory income tax rate $ 20.7 $ 19.9 $ 19.8 Adjustments to reconcile to income tax expense: State income taxes, net of federal benefit 2.6 3.1 3.3 Uncertain tax positions — 0.3 1.0 Nondeductible compensation 0.9 0.6 0.6 Nondeductible expenses, other than compensation 0.8 0.5 0.4 Valuation allowances 1.0 (0.4) 0.1 Basis difference in foreign investment 0.1 1.5 0.1 Foreign income taxes (1.5) (1.7) (0.5) Excess tax benefits related to stock compensation (0.1) (0.2) (0.5) Tax credits (2.3) (1.6) (1.8) Other (0.2) 2.5 (0.4) Income tax expense $ 22.0 $ 24.5 $ 22.1 The following table summarizes information concerning our gross unrecognized tax benefits. 2022 2021 (in millions) Balance at beginning of year $ 4.8 $ 4.5 Increase related to current year positions 0.7 0.6 Decrease related to current year positions (0.4) — Decrease as a result of statute of limitations lapse (0.3) (0.3) Foreign currency exchange losses (0.1) — Balance at end of year $ 4.7 $ 4.8 Substantially all unrecognized tax benefits would, if recognized, impact the effective tax rate. We recognize interest related to uncertain tax positions as interest expense and recognize any penalties incurred as a component of selling, general and administrative expenses. At September 30, 2022 and 2021, we had $0.7 million and $0.6 million, respectively, of accrued interest expense related to unrecognized tax benefits. Deferred income tax balances are presented below. September 30, 2022 2021 (in millions) Deferred income tax assets: Accrued expenses $ 10.5 $ 12.7 Lease liabilities 8.1 8.2 Inventories 7.0 6.1 State net operating losses 2.1 2.8 Net operating losses and credit carryovers 12.9 14.8 Stock-based compensation 4.1 3.8 Pension 0.1 — Other 2.3 2.9 Total deferred income tax assets 47.1 51.3 Valuation allowance (13.2) (13.6) Total deferred income tax assets, net of valuation allowance 33.9 37.7 Deferred income tax liabilities: Intangible assets 77.7 86.3 Lease assets 7.4 7.6 Basis difference in foreign investment 6.2 6.8 Pension — 3.9 Property, plant and equipment 28.4 27.4 Other 0.5 0.5 Total deferred income tax liabilities 120.2 132.5 Net deferred income tax liabilities $ 86.3 $ 94.8 We reevaluate the need for a valuation allowance against our deferred tax assets each quarter considering results to date, projections of taxable income, tax planning strategies and reversing taxable temporary differences. Our state net operating loss carryforwards, which expire between the years 2024 and 2032, remain available to offset future taxable earnings.

Borrowing Arrangements

Borrowing Arrangements	12 Months Ended
	Sep. 30, 2021
Long-Term Debt and Lease Obligation [Abstract]
Borrowing Arrangements	Borrowing Arrangements The components of our long-term debt are as follows: September 30, 2022 2021 (in millions) 4.0% Senior Notes $ 450.0 $ 450.0 Finance leases 1.6 2.2 Total debt 451.6 452.2 Less deferred financing costs (4.7) (5.3) Less current portion of long-term debt (0.8) (1.0) Long-term debt $ 446.1 $ 445.9 The scheduled maturities of all borrowings outstanding at September 30, 2022 for each of the following years are $0.8 million in 2023, $0.5 million in 2024, $0.3 million in 2025, $0 million in 2026 and $450.0 million thereafter. ABL Agreement . Our ABL Agreement, as amended, (“ABL”) is provided by a consortium of banking institutions and consists of a revolving credit facility for up to $175 million in borrowings that expires on July 29, 2025. Included in the ABL is the ability to borrow up to $25 million of swing line loans and up to $60 million of letters of credit. The ABL permits us to increase the size of the credit facility by an additional $150 million in certain circumstances subject to adequate borrowing base availability. Borrowings under the ABL bear interest at a floating rate equal to LIBOR plus an applicable margin range of 200 to 225 basis points, or a base rate, as defined in the ABL, plus an applicable margin range of 100 to 125 basis points. At September 30, 2022, the applicable margin was 200 basis points for LIBOR-based loans, and 100 basis points for base rate loans. The ABL is subject to mandatory prepayments if total outstanding borrowings under the ABL are greater than the aggregate commitments under the revolving credit facility or if we dispose of overdue accounts receivable in certain circumstances. The borrowing base under the ABL is equal to the sum of (a) 85% of the value of eligible accounts receivable and (b) the lesser of (i) 70% of the value of eligible inventory or (ii) 85% of the net orderly liquidation value of eligible inventory, less certain reserves. Prepayments can be made at any time without penalty. Substantially all of our United States subsidiaries are borrowers under the ABL and are jointly and severally liable for outstanding borrowings. Our obligations under the ABL are secured by a first-priority perfected lien on all of our United States inventory, accounts receivable, certain cash balances and other supporting obligations. The ABL includes a commitment fee for any unused borrowing capacity of 37.5 basis points per annum. Borrowings are not subject to any financial maintenance covenants unless excess availability is less than the greater of $17.5 million and 10% of the Loan Cap as defined in the ABL. Excess availability based on September 30, 2022 data was $160.7 million, as reduced by $14.1 million of outstanding letters of credit and $0.2 million of accrued fees and expenses. 4.0% Senior Unsecured Notes. On May 28, 2021, we privately issued $450.0 million of 4.0% Senior Notes, which mature on June 15, 2029 and bear interest at 4.0%, paid semi-annually in June and December. We capitalized $5.5 million of financing costs, which are being amortized over the term of the 4.0% Senior Notes using the effective interest method. Proceeds from the 4.0% Senior Notes, along with cash on hand were used to redeem our previously existing 5.5% Senior Notes. Substantially all of our United States subsidiaries guarantee the 4.0% Senior Notes, which are subordinate to borrowings under our ABL. Based on quoted market prices, which is a Level 1 measurement, the outstanding 4.0% Senior Notes had a fair value of $382.1 million as of September 30, 2022. An indenture securing the 4.0% Senior Notes (“Indenture”) contains customary covenants and events of default, including covenants that limit our ability to incur certain debt and liens. There are no financial maintenance covenants associated with the Indenture. We believe we were in compliance with these covenants at September 30, 2022. As set forth in the Indenture, we may redeem some or all of the 4.0% Senior Notes at any time prior to June 15, 2024 at certain “make-whole” redemption prices and on or after June 15, 2024, at specified redemption prices. Additionally, we may redeem up to 40% of the aggregate principal amount of the 4.0% Senior Notes at any time prior to June 15, 2024 with the net proceeds of specified equity offerings at specified redemption prices as set forth in the Indenture. Upon a change of control as defined in the Indenture, we would be required to offer to purchase the 4.0% Senior Notes at a price equal to 101% of the outstanding principal amount. 5.5% Senior Unsecured Notes. On June 12, 2018, we privately issued $450.0 million of 5.5% Senior Notes, which were set to mature in June 2026 and bore interest at 5.5%, paid semi-annually. We called the 5.5% Senior Notes effective June 17, 2021 and redeemed the 5.5% Senior Notes with the proceeds from the 4.0% Senior Notes and cash on hand. As a result, we incurred $16.7 million in loss on early extinguishment of debt, comprised of a $12.4 million call premium and a $4.3 million write-off of the remaining deferred debt issuance costs. .

Derivative Financial Instrument

Derivative Financial Instruments	12 Months Ended
	Sep. 30, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative Instruments and Hedging Activities Disclosure [Text Block]	Derivative Financial Instruments In connection with the acquisition of Singer Valve in 2017, we loaned funds to one of our Canadian subsidiaries. Although this intercompany loan has no direct effect on our consolidated financial statements, it creates exposure to currency risk for the Canadian subsidiary. To reduce this exposure, we entered into a United States dollar-Canadian dollar swap contract with the Canadian subsidiary and an offsetting Canadian dollar-United States dollar swap with a domestic bank, without designating these swap contracts as a hedge. As a result, the changes in the fair value of these contracts have been reported in earnings. As of September 30, 2021, we had a $1.1 million liability in Other current liabilities in our consolidated balance sheets related to such a hedge. These currency swap contracts expired

Retirement Plans

Retirement Plans	12 Months Ended
	Sep. 30, 2022
Retirement Benefits [Abstract]
Pension and Other Postretirement Benefits Disclosure	Retirement Plans Defined Benefit Plans. We have had various pension plans that we funded in accordance with their requirements and, where applicable, in amounts sufficient to satisfy the minimum funding requirements of applicable laws. Our pension plans provide benefits based on years of service and compensation or at stated amounts for each year of service with an annual measurement date as of September 30. After September 30, 2019, our only remaining defined benefit plan is our United States Pension Plan (“Pension Plan”). A summary of key assumptions for the valuations of our Pension Plan is as follows: September 30, 2022 2021 2020 Weighted average used to determine benefit obligations: Discount rate 5.79 % 3.01 % 2.84 % Weighted average used to determine net periodic cost: Discount rate 3.01 % 2.84 % 3.26 % Expected return on plan assets 4.50 % 4.50 % 5.00 % The discount rates for determining the present value of pension obligations were selected using a “bond settlement” approach, which constructs a hypothetical bond portfolio that could be purchased such that the coupon payments and maturity values could be used to satisfy the projected benefit payments. The discount rate is the equivalent rate that results in the present value of the projected benefit payments equaling the market value of this bond portfolio. Only high quality (AA graded or higher), non-callable corporate bonds are included in this bond portfolio. We rely on the Pension Plan’s actuaries to assist in the development of the discount rate model. The expected returns on plan assets are determined with the assistance of the Pension Plan’s actuaries and investment consultants. Expected returns on plan assets were developed using forward looking returns over a time horizon of 10 to 15 years for major asset classes along with projected risk and historical correlations. Amounts recognized for the Pension Plan are presented below. September 30, 2022 2021 (in millions) Projected benefit obligations: Beginning of year $ 336.8 $ 359.5 Service cost 1.3 1.5 Interest cost 9.8 9.9 Actuarial gain (74.0) (10.8) Benefits paid (22.7) (23.3) Accumulated benefit obligations at end of year $ 251.2 $ 336.8 Plan assets: Beginning of year $ 353.5 $ 360.4 Actual return on plan assets (79.0) 16.4 Benefits paid (22.7) (23.3) Fair value of plan assets at end of year $ 251.8 $ 353.5 Accrued benefit cost at end of year: Funded status $ 0.6 $ 16.8 Recognized on balance sheet: Other noncurrent assets $ 0.6 $ 16.8 Recognized in accumulated other comprehensive income (loss), before tax: Net actuarial loss 78.7 59.9 $ 78.7 $ 59.9 The components of net periodic (benefit) cost for our Pension Plan are presented below. 2022 2021 2020 (in millions) Service cost $ 1.3 $ 1.5 $ 1.5 Components of net periodic cost (benefit) excluded from operating income: Interest cost 9.8 9.9 11.2 Expected return on plan assets (15.4) (15.7) (16.9) Amortization of actuarial net loss 1.7 2.5 2.8 Other — — (0.1) Pension benefit other than service (3.9) (3.3) (3.0) Net periodic benefit $ (2.6) $ (1.8) $ (1.5) Pension Plan activity in accumulated other comprehensive loss, before tax, in 2022 is presented below, in millions. Balance at beginning of year $ 59.9 Actuarial loss 20.5 Prior year actuarial loss amortization to net periodic cost (1.7) Balance at end of year $ 78.7 We amortize amounts in accumulated other comprehensive loss representing unrecognized prior year service cost and unrecognized loss related to the Pension Plan over the weighted average life expectancy of their inactive participants. Actuarial gains and losses are amortized using a corridor approach. The gain/loss corridor is equal to 10% of the greater of the benefit obligation and the market-related value of assets. Gains and losses in excess of the corridor are generally amortized over the average remaining lifetime of the plan participants. We expect to amortiz e $3.7 million of unrecognized loss into net periodic expense from accumulated other comprehensive loss in 2023. Strategic asset allocations, tactical range at September 30, 2022 and actual asset allocations are as follows: Strategic asset allocation Actual asset allocations at September 30, Tactical range 2022 2021 2020 Fixed income investments 70 % 65 % - 70 % 70 % 70 % 78 % Equity investments 30 25 % - 30 % 29 29 21 Cash — 0 % - 5 % 1 1 1 100 % 100 % 100 % 100 % Assets of the Pension Plan are allocated to various investments to attain diversification and reasonable risk-adjusted returns while also managing the exposure to asset and liability volatility. These ranges are targets and deviations may occur from time to time as a result of market fluctuations. Portfolio assets are typically rebalanced to the allocation targets at least annually. The assets of the Pension Plan are primarily invested in mutual funds and investment trusts valued at net asset value, which in turn hold fixed income and equity investments. The valuation methodologies used to measure the assets of the Pension Plan at fair value are: • Mutual funds are valued at the closing price reported on the active market; • Fixed income fund investments held by the investment trusts are valued using the closing price reported in the active market in which the investment is traded. When market quotations are not readily available, these assets are valued by a method the trustees believe accurately reflects fair value. The assets of the Plan by level within the fair value hierarchy are as follows: September 30, 2022 Level 1 Level 2 Total (in millions) Fixed income $ 125.2 $ 50.1 $ 175.3 Equity: Large cap index funds 37.2 — 37.2 International stocks: International funds 37.4 — 37.4 Total equity 74.6 — 74.6 Cash and cash equivalents 1.9 — 1.9 $ 201.7 $ 50.1 $ 251.8 September 30, 2021 Level 1 Level 2 Total (in millions) Fixed income $ 176.7 $ 70.3 $ 247.0 Equity: Large cap index funds 52.1 — 52.1 International stocks: International funds 52.5 — 52.5 Total equity 104.6 — 104.6 Cash and cash equivalents 1.9 — 1.9 $ 283.2 $ 70.3 $ 353.5 Our estimated future pension benefit payments are presented below (in millions): 2023 $ 23.3 2024 23.1 2025 22.8 2026 22.4 2027 21.9 2028-2032 $ 100.7 Defined Contribution Retirement Plans. Certain of our employees participate in defined contribution 401(k) plans or similar plans outside of the United States. We make matching contributions as a function of employee contributions which were $7.3 million , $5.9 million and $5.3 million during 2022, 2021 and 2020, respectively.

Capital Stock

Capital Stock	12 Months Ended
	Sep. 30, 2022
Common Stock, Number of Shares, Par Value and Other Disclosure [Abstract]
Stockholders' Equity Note Disclosure	Capital Stock Common stock share activity is presented below. Shares outstanding at September 30, 2019 157,462,140 Vesting of restricted stock units, net of shares withheld for taxes 242,112 Exercise of stock options 534,291 Exercise of employee stock purchase plan instruments 182,971 Settlement of performance-based restricted stock units, net of shares withheld for taxes 61,610 Stock repurchased under buyback program (418,374) Shares outstanding at September 30, 2020 158,064,750 Vesting of restricted stock units, net of shares withheld for taxes 182,024 Exercise of stock options 151,399 Exercise of employee stock purchase plan instruments 146,135 Settlement of performance-based restricted stock units, net of shares withheld for taxes 62,396 Stock repurchased under buyback program (651,271) Shares outstanding at September 30, 2021 157,955,433 Vesting of restricted stock units, net of shares withheld for taxes 195,156 Exercise of stock options 36,731 Exercise of employee stock purchase plan instruments 150,909 Settlement of performance-based restricted stock units, net of shares withheld for taxes 160,163 Stock repurchased under buyback program (2,654,254) Shares outstanding at September 30, 2022 155,844,138 The Company has authorized 20.0 million shares of $0.01 par value preferred stock. The preferred stock may be issued in one or more series and with such designations and preferences for each series as shall be stated in the resolutions providing for the designation and issue of each such series adopted by the Board of Directors of the Company. The Board of Directors is authorized by the Company's articles of incorporation to determine the voting, dividend, redemption and liquidation preferences pertaining to each such series. No shares of preferred stock have been issued by the Company as of September 30, 2022.

Stock-based Compensation Plans

Stock-based Compensation Plans	12 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]
Share-based Payment Arrangement [Text Block]	Stock-based Compensation Plans The effect of stock-based compensation on our consolidated statements of operations is presented below. Such amounts are included within selling, general, and administrative costs. 2022 2021 2020 (in millions, except per share data) Decrease in operating income $ 9.9 $ 11.0 $ 7.2 Decrease in net income 7.6 8.2 5.5 Decrease in earnings per basic share 0.05 0.05 0.03 Decrease in earnings per diluted share 0.05 0.05 0.03 We excluded 790,759, 578,005 and 267,298 instruments from the calculation of diluted earnings per share for 2022, 2021 and 2020, respectively, because the effect of including them would have been antidilutive. At September 30, 2022, there was approximately $7.6 million of unrecognized compensation expense related to stock-based awards not yet vested. We expect to recognize this expense over a weighted average life of approximately 1.5 years. The Mueller Water Products, Inc. 2006 Stock Incentive Plan (“2006 Plan”) authorizes an aggregate of 20,500,000 shares of common stock that may be granted through the issuance of stock-based awards. Any awards canceled are available for reissuance. Generally, all of our employees and members of our Board of Directors are eligible to participate in the 2006 Plan. At September 30, 2022, 5,083,831 shares of common stock were available for future grants of awards under the 2006 Plan. This total assumes that the maximum number of shares will be earned for awards for which the final number of shares to be earned has not yet been determined. An award granted under the 2006 Plan vests at such times and in such installments as set by the Compensation and Human Resources Committee of our Board of Directors (“Compensation Committee”), but no award will be exercisable after the 10-year anniversary of the date on which it is granted. Management expects some instruments will be forfeited prior to vesting. Grants to members of our Board of Directors are expected to vest fully. Based on historical forfeitures, we expect grants to others to be forfeited at an annual rate of 2%. Restricted Stock Units. Depending on the specific terms of each award, restricted stock units generally vest ratably over the life of the award, usually three Restricted stock unit activity under the 2006 Plan is summarized below. Restricted stock units Weighted Weighted Aggregate Outstanding at September 30, 2019 437,022 $ 11.31 0.9 Granted 301,979 11.55 Vested (295,241) 11.40 $ 3.4 Cancelled (35,254) 11.48 Outstanding at September 30, 2020 408,506 11.41 0.9 Granted 220,795 12.29 Vested (228,121) 11.62 $ 2.8 Cancelled (5,083) 11.41 Outstanding at September 30, 2021 396,097 11.78 0.8 Granted 223,379 13.41 Vested (251,981) 11.81 $ 2.8 Cancelled (8,763) 11.87 Outstanding at September 30, 2022 358,732 $ 12.77 0.7 Performance-Based Awards. Our performance-based awards consist of performance-based restricted stock units (“PRSUs”). PRSUs represent a target number of units that may be paid out at the end of a multi-year award cycle consisting of annual performance periods coinciding with our fiscal years. As determined at the date of award, PRSUs may settle in cash-value equivalent of, or directly in, shares of our common stock. Settlement will range from zero to two times the number of PRSUs granted, depending on our financial performance against predetermined targets. The grant date for each year’s performance period is set when the Compensation Committee establishes performance goals for the period, normally within 90 days of the beginning of each performance period. At the end of each annual performance period, the Compensation Committee confirms performance against the applicable performance targets. PRSUs do not convey voting rights or earn dividends. PRSUs vest on the last day of an award cycle, unless vested sooner as a result of a “Change of Control” of the Company, or the death, disability or Retirement of a participant. We recognize compensation expense for stock-settled PRSUs starting on the first day of the applicable performance period and ending on the respective vesting dates. We base the recognized compensation expense upon the number of units awarded for each performance period, the closing price of our common stock on the grant date and the estimated performance factor. In 2022 and 2021, 240,412 shares and 103,058 shares, respectively, vested related to PRSUs. Stock-settled PRSUs activity under the 2006 Plan is summarized below. Award date Settlement year Performance period Grant date per unit fair value Units Units forfeited Net units Performance factor Shares November 29, 2016 2020 2017 $ 13.26 59,285 (5,279) 54,006 1.000 54,006 2018 $ 12.50 59,286 (39,910) 19,376 1.357 26,294 2019 $ 10.53 59,290 (39,909) 19,381 0.645 12,501 January 23, 2017 2020 2017 $ 13.15 19,012 — 19,012 1.000 19,012 2018 $ 12.50 19,011 — 19,011 1.357 25,798 2019 $ 10.53 19,011 — 19,011 0.645 12,263 November 28, 2017 2021 2018 $ 12.50 57,092 — 57,092 1.357 77,474 2019 $ 10.53 57,092 (4,793) 52,299 0.645 33,733 2020 $ 11.26 57,104 (21,679) 35,425 0.909 32,202 November 27, 2018 2022 2019 $ 10.53 110,954 (8,751) 102,203 0.645 65,921 2020 $ 11.26 110,954 (13,182) 97,772 0.909 88,875 2021 $ 11.86 110,967 (28,478) 82,489 1.161 95,770 December 3, 2019 2023 2020 $ 11.26 69,988 (2,391) 67,597 0.909 61,446 2021 $ 11.86 69,989 (9,614) 60,375 1.161 70,096 2022 $ 13.81 69,988 (9,614) 60,374 0.700 42,262 Market-Based Awards. Our market-based awards consist of market-based restricted stock units (“MRSUs”). MRSUs represent a target number of units that may be paid out at the end of a three-fiscal year award cycle based on a calculation of our relative total shareholder return (“TSR”) performance as compared with the TSRs of a selected peer group. Settlements in our common shares, will range from zero to two times the number of MRSUs granted, depending on our TSR performance ranking within the peer group. The fair values of MRSUs are fixed at the date of grant and the related expense is recognized ratably over the vesting period, which is roughly three years from the date of grant. The table below provides information regarding MRSU awards, which were valued using Monte Carlo simulations on the grant date. November 30, 2021 January 27, 2021 December 2, 2020 February 24, 2020 January 28, 2020 December 3, 2019 Fair value at grant date $ 15.76 $ 14.26 $ 15.39 $ 18.17 $ 16.76 $ 14.94 Units granted 230,089 4,187 234,199 7,498 2,763 147,213 Variables used in determining grant date fair value: Dividend yield 1.70 % 1.84 % 1.77 % 1.73 % 1.76 % 1.87 % Risk-free rate 0.76 % 0.16 % 0.21 % 1.23 % 1.44 % 1.53 % Expected term (in years) 2.83 2.67 2.83 2.60 2.67 2.83 Stock Options. Stock options generally vest on each anniversary date of the original grant ratably over three years. Compensation expense attributed to stock options is based on the fair value of the awards on their respective grant dates, as determined using a Black-Scholes model. The assumptions used to determine the grant date fair value are indicated below for grants issued during our 2022 fiscal year. November 30, 2021 Variables used in determining grant date fair value: Dividend yield 1.62% Risk-free rate 1.33% Expected term (in years) 6.0 The expected dividend yield is based on our estimated annual dividend and our stock price history at the grant date. The risk-free interest rate is based on the United States Treasury zero-coupon yield in effect at the grant date with a term equal to the expected term. The expected term represents the average period of time the options are expected to be outstanding. Stock option activity under the 2006 Plan is summarized below. Options Weighted Weighted Aggregate Outstanding at September 30, 2019 862,390 $ 4.89 2.0 $ 5.5 Exercised (534,291) 4.15 3.3 Cancelled — — Outstanding at September 30, 2020 328,099 $ 6.11 2.3 $ 1.4 Granted 431,520 11.86 Exercised (151,399) 4.09 1.7 Cancelled (8,421) — Outstanding at September 30, 2021 599,799 $ 10.67 7.8 $ 2.7 Granted 457,482 13.64 Exercised (36,731) 5.67 0.2 Cancelled (7,257) — Outstanding at September 30, 2022 1,013,293 $ 12.19 7.7 $ 0.3 Exercisable at September 30, 2022 278,569 $ 10.12 4.8 $ 0.3 Stock option exercise prices are equal to the closing price of our common stock on the relevant grant date. The ranges of exercise prices for stock options outstanding at September 30, 2022 are summarized below. Exercise price Options Weighted Weighted Exercisable options Weighted $ 5.00 - $ 9.99 139,969 8.40 1.4 139,969 8.40 $10.00 - $14.99 873,324 $ 12.79 8.7 138,600 $ 11.86 1,013,293 $ 12.19 7.7 278,569 $ 10.12 Employee Stock Purchase Plan. The Mueller Water Products, Inc. 2006 Employee Stock Purchase Plan (“ESPP”) authorizes the sale of up to 5,800,000 shares of our common stock to employees. Generally, all full-time, active employees are eligible to participate in the ESPP, subject to certain restrictions. Employee purchases are funded through payroll deductions, and any excess payroll withholdings are returned to the employee. The price for shares purchased under the ESPP is 85% of the lower of the closing price on the first day or the last day of the offering period. At September 30, 2022, 2,103,114 shares were available for issuance under the ESPP. Phantom Plan. Under the Mueller Water Products, Inc. Phantom Plan adopted in 2012 (“Phantom Plan”), we have awarded “phantom units” to certain non-officer employees. A phantom unit settles in cash equal to the price of one share of our common stock on the vesting date. Phantom units vest ratably over three Phantom Plan activity is summarized below. Phantom Weighted Weighted Aggregate Outstanding at September 30, 2019 256,154 $ 11.61 0.9 Granted 188,973 11.26 Vested (118,908) $ 1.3 Cancelled (11,744) 11.23 Outstanding at September 30, 2020 314,475 11.16 0.9 Granted 185,808 11.91 Vested (131,182) $ 1.6 Cancelled (24,257) 11.30 Outstanding at September 30, 2021 344,844 11.51 0.9 Granted 203,834 13.60 Vested (162,969) $ 1.6 Cancelled (46,578) 12.39 Outstanding at September 30, 2022 339,131 $ 12.74 1.1

Segment Information

Segment Information	12 Months Ended
	Sep. 30, 2022
Segment Reporting [Abstract]
Segment Reporting Disclosure [Text Block]	Segment Information We adopted a new management structure effective October 1, 2021 which resulted in a change to our reportable segments. Prior period information has been recast to conform to the current presentation. The recasting has no effect on our previously reported consolidated balance sheets, consolidated statements of operations, or consolidated statements of cash flows. The two newly named business units and reportable segments are Water Flow Solutions and Water Management Solutions. Water Flow Solutions’ product portfolio includes iron gate valves, specialty valves and service brass products. Water Management Solutions’ product and service portfolio includes fire hydrants, repair and installation, natural gas, metering, leak detection, pressure control and software products. Segment results are not reflective of their results on a stand-alone basis. Intersegment sales and transfers are made at selling prices generally intended to cover costs. The determination of segment results excludes certain expenses designated as Corporate because they are not directly attributable to segment operations. Interest expense, loss on early extinguishment of debt and income taxes are not allocated to the segments. Corporate expenses include those costs incurred by our corporate function, such as accounting, treasury, risk management, human resources, legal, tax and other administrative functions. Corporate assets principally consist of our cash, operating lease assets, and certain real property previously owned by U.S. Pipe and Anvil. Business segment assets consist primarily of receivables, inventories, property, plant and equipment, intangible assets and other noncurrent assets. The Company has two significant customers that comprise greater than 10% of our gross sales. One customer comprised 21%, 18%, and 17% of consolidated revenues for the fiscal years ended September 30, 2022, 2021, and 2020, respectively. The Company has outstanding accounts receivable from this customer of $52.1 million and $48.1 million as of September 30, 2022 and 2021, respectively. Another customer comprised 20%, 19%, and 17% of consolidated revenues for the fiscal years ended September 30, 2022, 2021, and 2020, respectively. The Company has outstanding accounts receivable from this customer of $38.6 million and $32.1 million as of September 30, 2022 and 2021, respectively. The Company reports revenue for these customers in both reportable segments, Water Flow Sol utions and Water Management Solutions. Geographical area information is presented below. United States Israel Other Total (in millions) Property, plant and equipment, net: September 30, 2022 $ 284.9 $ 12.6 $ 4.1 $ 301.6 September 30, 2021 263.9 13.8 5.7 283.4 Year ended September 30, 2022 2021 2020 (in millions) Water Flow Solutions disaggregated net revenues: Central $ 190.9 $ 155.1 $ 133.6 Northeast 125.3 110.4 95.1 Southeast 154.3 125.7 108.3 West 182.8 172.4 148.5 United States $ 653.3 $ 563.6 $ 485.5 Canada 55.0 45.7 39.4 Other international locations 5.8 8.5 7.3 $ 714.1 $ 617.8 $ 532.2 Water Management Solutions disaggregated net revenues: Central $ 142.9 $ 125.6 $ 107.3 Northeast 115.1 100.2 112.1 Southeast 109.4 106.5 76.3 West 102.9 99.1 81.8 United States $ 470.3 $ 431.4 $ 377.5 Canada 39.2 38.1 33.4 Other international locations 23.8 23.7 21.0 $ 533.3 $ 493.2 $ 431.9 Summarized financial information for our segments is presented below. Water Flow Water Management Corporate Total (in millions) Net revenue: 2022 $ 714.1 $ 533.3 $ — $ 1,247.4 2021 617.8 493.2 — 1,111.0 2020 532.2 431.9 — 964.1 Operating income (loss): 2022 $ 118.3 $ 48.7 $ (55.4) $ 111.6 2021 120.9 70.3 (59.5) 131.7 2020 104.9 68.7 (56.8) 116.8 Depreciation and amortization: 2022 $ 30.0 $ 30.3 $ 0.2 $ 60.5 2021 30.5 28.9 0.2 59.6 2020 28.9 28.7 0.2 57.8 Strategic reorganization and other charges: 2022 $ 0.2 $ 0.4 $ 6.6 $ 7.2 2021 0.1 (0.4) 8.3 8.0 2020 — 0.7 12.3 13.0 Capital expenditures: 2022 $ 43.4 $ 11.3 $ — $ 54.7 2021 51.0 11.6 0.1 62.7 2020 57.3 10.1 0.3 67.7 Intangible assets, net and goodwill September 30, 2022 $ 302.6 $ 157.2 $ — $ 459.8 September 30, 2021 324.1 183.5 — 507.6 Inventories, net: September 30, 2022 $ 160.5 $ 118.2 $ — 278.7 September 30, 2021 $ 104.5 $ 80.2 $ — 184.7

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Sep. 30, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments And Contingencies	Commitments and Contingencies We are involved in various legal proceedings that have arisen in the normal course of operations, including the proceedings summarized below. We provide for costs relating to these matters when a loss is probable and the amount is reasonably estimable. Legal and administrative costs related to these matters are expensed as incurred. The effect of the outcome of these matters on our financial statements cannot be predicted with certainty as any such effect depends on the amount and timing of the resolution of such matters. Other than the litigation described below, we do not believe that any of our outstanding litigation would have a materially adverse effect on our financial position, results of operations, cash flows or liquidity. Environmental. We are subject to a wide variety of laws and regulations concerning the protection of the environment, both with respect to the operations at many of our properties and with respect to remediating environmental conditions that may exist at our own or other properties. We accrue for environmental expenses resulting from existing conditions that relate to past operations when the costs are probable and reasonably estimable. In the acquisition agreement pursuant to which a predecessor to Tyco International plc, now Johnson Controls International plc (“Tyco”), sold our businesses to a previous owner in August 1999, Tyco agreed to indemnify us and our affiliates, among other things, for all “Excluded Liabilities.” Excluded Liabilities include, among other things, substantially all liabilities relating to the time prior to August 1999, including environmental liabilities. The indemnity survives indefinitely. Tyco’s indemnity does not cover liabilities to the extent caused by us or the operation of our businesses after August 1999, nor does it cover liabilities arising with respect to businesses or sites acquired after August 1999. Since 2007, Tyco has engaged in multiple corporate restructurings, split-offs and divestitures. While none of these transactions directly affects the indemnification obligations of the Tyco indemnitors under the 1999 acquisition agreement, the result of such transactions is that the assets of, and control over, such Tyco indemnitors has changed. Should any of these Tyco indemnitors become financially unable or fail to comply with the terms of the indemnity, we may be responsible for such obligations or liabilities. On July 13, 2010, Rohcan Investments Limited, the former owner of property leased by Mueller Canada Ltd. and located in Milton, Ontario, filed suit in the Ontario Superior Court of Justice against Mueller Canada Ltd. and its directors seeking C$10.0 million in damages arising from the defendants’ alleged environmental contamination of the property and breach of lease. Mueller Canada Ltd. leased the property from 1988 through 2008. We are pursuing indemnification from a former owner for certain potential liabilities that are alleged in this lawsuit, and we have accrued for other liabilities not covered by indemnification. On December 7, 2011, the Court denied the plaintiff’s motion for summary judgment. The purchaser of U.S. Pipe has been identified as a “potentially responsible party” (“PRP”) under the Comprehensive Environmental Response, Compensation and Liability Act in connection with a former manufacturing facility operated by U.S. Pipe that was in the vicinity of a proposed Superfund site located in North Birmingham, Alabama. Under the terms of the acquisition agreement relating to our sale of U.S. Pipe, we agreed to indemnify the purchaser for certain environmental liabilities, including those arising out of the former manufacturing site in North Birmingham. Accordingly, the purchaser tendered the matter to us for indemnification, which we accepted. Ultimate liability for the site will depend on many factors that have not yet been determined, including the determination of the Environmental Protection Agency’s remediation costs, the number and financial viability of the other PRPs (there are four other PRPs currently) and the determination of the final allocation of the costs among the PRPs. Since the amounts of such costs cannot be reasonably estimated at this time, no amounts have been accrued for this matter at September 30, 2022. The COVID-19 Pandemic. The pandemic has caused, and is likely to continue to cause, severe economic, market and other disruptions to the U.S. and global economies. We have taken action and continue to counter such disruption, and work to protect the safety of our employees. While the extent to which the pandemic affects our results will depend on future developments, the pandemic could result in material effects to our future financial position, results of operations, cash flows and liquidity. Mass Shooting Event at our Facility in Albertville, Alabama . On June 15, 2021, we exp erienced a mass shooting event at our facility in Albertville, Alabama. Various claims arising from the event have been filed to date, some of which have been resolved, and we anticipate that additional claims may be made. Liability under such claims, if any, is not expected to have a material adverse effect on our results of operations or cash flows. However, the outcome of outstanding and potential claims, legal proceedings and related effects arising from this event cannot be predicted with certainty. Indemnifications . We are a party to contracts in which it is common for us to agree to indemnify third parties for certain liabilities that arise out of or relate to the subject matter of the contract. In some cases, this indemnity extends to related liabilities arising from the negligence of the indemnified parties, but usually excludes any liabilities caused by gross negligence or willful misconduct. We cannot estimate the potential amount of future payments under these indemnities until events arise that would trigger a liability under the indemnities. Additionally, in connection with the sale of assets and the divestiture of businesses, such as the divestitures of U.S. Pipe and Anvil, we may agree to indemnify buyers and related parties for certain losses or liabilities incurred by these parties with respect to: (i) the representations and warranties made by us to these parties in connection with the sale and (ii) liabilities related to the pre-closing operations of the assets or business sold. Indemnities related to pre-closing operations generally include certain environmental and tax liabilities and other liabilities not assumed by these parties in the transaction. Indemnities related to the pre-closing operations of sold assets or businesses normally do not represent additional liabilities to us, but simply serve to protect these parties from potential liability associated with our obligations existing at the time of the sale. As with any liability, we have accrued for those pre-closing obligations that are considered probable and reasonably estimable. Should circumstances change, increasing the likelihood of payments related to a specific indemnity, we will accrue a liability when future payment is probable and the amount is reasonably estimable. Other Matters. We monitor and analyze our warranty experience and costs periodically and may revise our accruals as necessary. Critical factors in our 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. We are party to a number of lawsuits arising in the ordinary course of business, including product liability cases for products manufactured by us or third parties. While the results of litigation cannot be predicted with certainty, we believe that the final outcome of such other litigation is not likely to have a materially adverse effect on our financial position, results of operations, cash flows or liquidity.

Subsequent Events

Subsequent Events	12 Months Ended
	Sep. 30, 2022
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Dividend Declaration. On October 21, 2022, our Board of Directors declared a dividend of $0.061 per share on our common stock, payable on or about November 21, 2022 to stockholders of record at the close of business on November 10, 2022. Collective Bargaining Agreement Extension.

Leases, Codification Topic 842

Leases, Codification Topic 842	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Leases Of Lessee Operating Leases And Finance Leases Disclosure	Leases On October 1, 2019, we adopted ASC 842 - Leases utilizing the modified retrospective approach. Adoption of the new standard resulted in an increase to total assets and liabilities as a result of recording lease right-of-use assets (“ROU”) and lease liabilities related to our operating lease portfolio. We elected three practical expedients for transition, which include the carry forward of our leases without reassessing whether any contracts are leases or contain leases, lease classification and initial direct costs as well as applying hindsight when determining the lease term and when assessing impairment of ROU assets at the adoption date. This allows us to update our assessments according to new information and changes in facts and circumstances that have occurred since lease inception. Presentation of Leases We lease certain office, warehouse, manufacturing, distribution, and research and development facilities and equipment under operating leases. Our leases have remaining lease terms of up to 12 years. The terms and conditions of our leases may include options to extend or terminate the lease which are considered and included in the lease term when these options are reasonably certain of exercise. We determine if a contract is, or contains, a lease at inception by evaluating whether the contract conveys the right to control the use of an identified asset. For all classes of leased assets, we have elected the practical expedient to account for any non-lease components in the contract together with the related lease component in the same unit of account. ROU assets and lease liabilities are recognized in our consolidated balance sheets at the commencement date based on the present value of remaining lease payments over the lease term. Additionally, ROU assets include any lease payments made at or before the commencement date, as well as any initial direct costs incurred, and are reduced by any lease incentives received. As most of our operating leases do not provide an implicit rate, we apply our incremental borrowing rate to determine the present value of remaining lease payments. Our incremental borrowing rate is determined based on information available at the commencement date of the lease. For all classes of leased assets, we have applied an accounting policy election to exclude short-term leases from recognition in our consolidated balance sheets. A short-term lease has a lease term of 12 months or less at the commencement date and does not include a purchase option that is reasonably certain of exercise. We recognize short-term lease expense in our condensed consolidated statements of operations on a straight-line basis over the lease term. Our short-term lease expense for the years ended September 30, 2022 and 2021 and short-term lease commitments at September 30, 2022 are immaterial. We have certain lease contracts with terms and conditions that provide for variability in the payment amount based on changes in facts or circumstances occurring after the commencement date. These variable lease payments are recognized in our consolidated statements of operations as the obligation is incurred. At September 30, 2022, any legally-binding minimum lease payments for operating leases signed but not yet commenced, subleases, leases that imposed significant restrictions or covenants, related party leases or sale-leaseback arrangements were immaterial. The components of lease cost are presented below. Year ended September 30, 2022 2021 2020 (in millions) Operating lease cost $ 5.8 $ 6.1 $ 6.3 Finance lease cost 1.3 1.2 1.3 Total lease expense $ 7.1 $ 7.3 $ 7.6 Supplemental cash flow information related to leases are presented below, in millions. Year ended September 30, 2022 2021 Operating cash used for operating leases $ 5.8 $ 6.1 Financing cash used for finance leases $ 1.3 $ 1.2 Supplemental information regarding our lease assets and liabilities is below. September 30, 2022 2021 (in millions) Right-of-use assets: Operating leases Other noncurrent assets $ 26.0 $ 27.1 Finance leases Plant, property and equipment 1.4 2.2 Total right-of-use assets $ 27.4 $ 29.3 Lease liabilities: Operating leases - current Other current liabilities $ 4.4 $ 4.0 Operating leases - noncurrent Other noncurrent liabilities 22.4 24.6 Finance leases - current Current portion of long-term debt 0.8 1.0 Finance leases - noncurrent Long-term debt 0.8 1.2 Total lease liabilities $ 28.4 $ 30.8 Supplemental information related to lease terms and discount rates are presented below. Year ended September 30, 2022 2021 Weighted-average remaining lease term (years): Operating leases 6.67 7.82 Finance leases 2.15 2.53 Weighted-average interest rate: Operating leases 5.48 % 5.36 % Finance leases 3.64 % 4.24 % Total lease liabilities at September 30, 2022 have scheduled maturities as follows: Operating Leases Finance Leases (in millions) 2023 $ 5.9 $ 0.9 2024 5.7 0.5 2025 5.1 0.2 2026 4.7 0.1 2027 3.9 — Thereafter 7.3 — Total lease payments 32.6 1.7 Less: imputed interest (5.8) (0.1) Present value of lease liabilities $ 26.8 $ 1.6

Other Income and Expenses

Other Income and Expenses	12 Months Ended
	Sep. 30, 2022
Other Income and Expenses [Abstract]
Other Income and Other Expense Disclosure	Supplemental Statement of Operations Information Between November 2019 a nd March 2021, we announced the purchase and closure of several facilities. We purchased a new facility in Kimball, Tennessee, to support and enhance our investment in our Chattanooga, Tennessee large casting foundry and closed our facilities in Hammond, Indiana and Woodland, Washington. We also completed the closures of our facilities in Aurora, Illinois and Surrey, British Columbia, Canada during our fiscal year 2022. The majority of the activities from these plants were transferred to our Kimball, Tennessee facility. We incurred $1.5 million and $5.6 million of expenses, respectively, for the years ended September 30, 2022, and 2021, as a result of these plant closures. The $5.6 million incurred during fiscal 2021 included approximately $3.2 million of termination benefit costs which are included in Strategic reorganization and other charges and approximately $2.4 million in inventory write-downs which are included in Cost of sales in our consolidated statements of operations. Additionally, fiscal year 2022 included Strategic reorganization and other charges related to the Albertville tragedy and certain transaction-related costs. Fiscal year 2021 included Strategic reorganization and other charges related to the Albertville tragedy, and certain transaction costs, partially offset by a one-time settlement gain in connection with an indemnification from a previously owned property. Activity in accrued restructuring, reported as part of other current liabilities, is presented below. 2022 2021 2020 (in millions) Beginning balance $ 3.1 $ 2.8 $ 1.7 Expenses incurred $ 7.2 $ 5.4 $ 4.8 Amounts paid $ (7.0) $ (5.1) $ (3.7) Ending balance $ 3.3 $ 3.1 $ 2.8 Selected supplemental statement of operations information is presented below. 2022 2021 2020 (in millions) Included in selling, general and administrative expenses: Research and development $ 24.5 $ 17.1 $ 15.0 Advertising $ 5.5 $ 3.2 $ 3.3 Interest expense, net: 5.5% Senior Notes $ — $ 17.6 $ 24.8 4.0% Senior Notes 18.0 6.2 — Deferred financing costs amortization 1.0 1.1 1.2 ABL Agreement 0.9 0.9 0.6 Capitalized interest (2.6) (2.3) (0.3) Other interest expense 0.3 0.3 0.3 Total interest expense 17.6 23.8 26.6 Interest income (0.7) (0.4) (1.1) Net interest expense $ 16.9 $ 23.4 $ 25.5

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
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 12. for more information regarding our stock-based compensation.
Cash and Cash Equivalents	Cash and Cash Equivalents. All highly liquid investments with remaining 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, letters of credit, bonds or other instruments are required to ensure payment.
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
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 15 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 internal-use software are capitalized. Capitalized costs are depreciated over the estimated useful life of the system or software, generally six 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, 2022 and 2021, asset retirement obligations were $3.6 million and $3.8 million, respectively.
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 6. 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 $11.1 million as of September 30, 2022, and we expect to recover $5.9 million in insurance which is included as a receivable in Other current assets and Other noncurrent assets as of September 30, 2022. As of September 30, 2021, our gross worker’s compensation liability was $10.5 million and our insurance receivable was 3.5 million.
Warranty Costs			Warranty Costs. We accrue for warranty expenses, which include costs of repair and/or replacement, 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. Critical factors 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. Debt issuance 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 N MTC transaction, are included in Other noncurrent assets consistent with the life of the instrument. Deferred financing costs of $5.6 million at September 30, 2022 are scheduled to amortize as follows: $0.7 million related to the ABL, $0.3 million related to the NMTC transaction which are amortized on a straight-line basis and; $4.6 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 8. for disclosures related to our borrowing arrangements.
Derivative Instruments and Hedging Activities	Derivative Instruments and Hedging Activities. We manage U.S. dollar - Canadian dollar exchange rate risk related to intercompany loans with swap contracts from time to time without designating these swap contracts as a hedge. As a result, the changes in the fair value of these contracts have been reported in earnings. As of September 30, 2021, we had a $1.1 million liability in Other current liabilities in our consolidated balance sheets related to such a hedge. These currency swap contracts expired
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 17. 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 During 2016, the Financial Accounting Standards Board (“FASB”) issued standard Accounting Standard Codification (“ASC”) 326 - Current Expected Credit Losses (“ASC 326”) to replace the “incurred loss” impairment approach with an “expected loss” approach. This requires consideration of a broader range of reasonable and supportable information to estimate credit losses. We have completed historical and forward-looking analyses for receivables and adopted this guidance effective October 1, 2020. Upon adoption, there was no material impact to our financial statements. 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”). The new guidance 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, can 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 ASU 2022-03 Fair Value Measurement (Topic 820): Fair Value Measurement of Equity Securities Subject to Contractual Sale Restrictions: The FASB issued this update in June 2022, 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. Management does not expect that changes required by the new standard will have a material impact on our financial statements and related disclosures.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Accounting Policies [Abstract]
Financing Receivable, Current, Allowance for Credit Loss [Table Text Block]		The following table summarizes information concerning our allowance for credit losses. 2022 2021 2020 (in millions) Balance at beginning of year $ 3.5 $ 2.5 $ 1.5 Provision charged to expense 2.5 1.1 1.1 Other (0.4) (0.1) (0.1) Balance at end of year $ 5.6 $ 3.5 $ 2.5
Schedule of Reserves for Excess and Obsolete Inventory		The following table summarizes information concerning our inventory valuation reserves. 2022 2021 2020 (in millions) Balance at beginning of year $ 14.8 $ 11.7 $ 7.5 Provision charged to expense 1.8 5.9 4.7 Inventory disposed (1.4) (3.6) (0.7) Other 1.3 0.8 0.2 Balance at end of year $ 16.5 $ 14.8 $ 11.7
Schedule of Product Warranty Liability	Activity in our accrued warranty, reported as part of both other current liabilities and other noncurrent liabilities, is presented below. 2022 2021 2020 (in millions) Balance at beginning of year $ 9.7 $ 14.4 $ 17.1 Warranty accruals 9.5 3.5 2.6 Warranty costs (8.5) (8.2) (5.3) Balance at end of year $ 10.7 $ 9.7 $ 14.4

Business Combination (Tables)

Business Combination (Tables)	12 Months Ended
	Sep. 30, 2022
Business Combinations [Abstract]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]	The following is a summary of the fair values of the net assets acquired (in millions): Assets, net of cash: Receivables $ 0.5 Inventories 0.6 Other current assets 0.9 Identified intangible assets: Tradename 1.8 Customer relationships 2.1 Non-compete agreements 0.1 Developed technology 3.5 Goodwill 12.1 Liabilities: Accounts payable (0.8) Other current liabilities (1.3) Fair value of net assets acquired, net of cash $ 19.5

Identifiable Intangible Assets

Identifiable Intangible Assets (Tables)	12 Months Ended
	Sep. 30, 2022
Goodwill [Line Items]
Schedule of Goodwill [Table Text Block]	Changes in the carrying amount of goodwill for the years ended September 30, 2022 and 2021 were as follows:
Schedule of Intangible Assets and Goodwill [Table Text Block]	Intangible assets are presented below. September 30, 2022 2021 (in millions) Capitalized internal-use software: Cost $ 35.5 $ 34.1 Accumulated amortization (26.8) (24.1) Capitalized internal-use software, net $ 8.7 $ 10.0 Business combination-related: Cost: Finite-lived intangible assets: Technology 119.9 123.5 Customer relationships and other 371.6 373.0 Indefinite-lived intangible assets: Trade names and trademarks 272.7 273.8 $ 764.2 $ 770.3 Accumulated amortization: Technology (89.5) (85.8) Customer relationships and other (322.2) (302.0) (411.7) (387.8) Business combination-related intangible assets, net 352.5 382.5 Intangible assets, net $ 361.2 $ 392.5

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Sep. 30, 2022
Income Tax Disclosure [Abstract]
Schedule of Income before Income Tax, Domestic and Foreign	The components of income before income taxes are presented below. 2022 2021 2020 (in millions) U.S. $ 81.6 $ 94.0 $ 89.7 Non-U.S. 17.0 0.9 4.4 Income before income taxes $ 98.6 $ 94.9 $ 94.1
Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]	The components of income tax expense are as follows: 2022 2021 2020 (in millions) Current: U.S. federal $ 19.5 $ 21.9 $ 10.9 U.S. state and local 4.3 6.3 2.7 Non-U.S. 1.7 1.6 1.3 Total current income tax expense 25.5 29.8 14.9 Deferred: U.S. federal (3.4) (4.7) 5.6 U.S. state and local (0.9) (1.3) 2.0 Non-U.S. 0.8 0.7 (0.4) Total deferred income tax (benefit) expense (3.5) (5.3) 7.2 Income tax expense $ 22.0 $ 24.5 $ 22.1
Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]	The reconciliation between income tax expense at the United States federal statutory income tax rate and reported income tax expense is presented below. 2022 2021 2020 (in millions) Expense at U.S. federal statutory income tax rate $ 20.7 $ 19.9 $ 19.8 Adjustments to reconcile to income tax expense: State income taxes, net of federal benefit 2.6 3.1 3.3 Uncertain tax positions — 0.3 1.0 Nondeductible compensation 0.9 0.6 0.6 Nondeductible expenses, other than compensation 0.8 0.5 0.4 Valuation allowances 1.0 (0.4) 0.1 Basis difference in foreign investment 0.1 1.5 0.1 Foreign income taxes (1.5) (1.7) (0.5) Excess tax benefits related to stock compensation (0.1) (0.2) (0.5) Tax credits (2.3) (1.6) (1.8) Other (0.2) 2.5 (0.4) Income tax expense $ 22.0 $ 24.5 $ 22.1
Schedule of Deferred Tax Assets and Liabilities	Deferred income tax balances are presented below. September 30, 2022 2021 (in millions) Deferred income tax assets: Accrued expenses $ 10.5 $ 12.7 Lease liabilities 8.1 8.2 Inventories 7.0 6.1 State net operating losses 2.1 2.8 Net operating losses and credit carryovers 12.9 14.8 Stock-based compensation 4.1 3.8 Pension 0.1 — Other 2.3 2.9 Total deferred income tax assets 47.1 51.3 Valuation allowance (13.2) (13.6) Total deferred income tax assets, net of valuation allowance 33.9 37.7 Deferred income tax liabilities: Intangible assets 77.7 86.3 Lease assets 7.4 7.6 Basis difference in foreign investment 6.2 6.8 Pension — 3.9 Property, plant and equipment 28.4 27.4 Other 0.5 0.5 Total deferred income tax liabilities 120.2 132.5 Net deferred income tax liabilities $ 86.3 $ 94.8
Schedule of Unrecognized Tax Benefits Roll Forward	The following table summarizes information concerning our gross unrecognized tax benefits. 2022 2021 (in millions) Balance at beginning of year $ 4.8 $ 4.5 Increase related to current year positions 0.7 0.6 Decrease related to current year positions (0.4) — Decrease as a result of statute of limitations lapse (0.3) (0.3) Foreign currency exchange losses (0.1) — Balance at end of year $ 4.7 $ 4.8

Borrowing Arrangements (Tables)

Borrowing Arrangements (Tables)	12 Months Ended
	Sep. 30, 2022
Long-Term Debt and Lease Obligation [Abstract]
Components of Long-Term Debt	The components of our long-term debt are as follows: September 30, 2022 2021 (in millions) 4.0% Senior Notes $ 450.0 $ 450.0 Finance leases 1.6 2.2 Total debt 451.6 452.2 Less deferred financing costs (4.7) (5.3) Less current portion of long-term debt (0.8) (1.0) Long-term debt $ 446.1 $ 445.9

Retirement Plans (Tables)

Retirement Plans (Tables)	12 Months Ended
	Sep. 30, 2022
Retirement Benefits [Abstract]
Schedule of Net Periodic Benefit Cost	The components of net periodic (benefit) cost for our Pension Plan are presented below. 2022 2021 2020 (in millions) Service cost $ 1.3 $ 1.5 $ 1.5 Components of net periodic cost (benefit) excluded from operating income: Interest cost 9.8 9.9 11.2 Expected return on plan assets (15.4) (15.7) (16.9) Amortization of actuarial net loss 1.7 2.5 2.8 Other — — (0.1) Pension benefit other than service (3.9) (3.3) (3.0) Net periodic benefit $ (2.6) $ (1.8) $ (1.5)
Schedule of Accumulated and Projected Benefit Obligations	P
Schedule Of Defined Benefit Plans Disclosures	Amounts recognized for the Pension Plan are presented below. September 30, 2022 2021 (in millions) Projected benefit obligations: Beginning of year $ 336.8 $ 359.5 Service cost 1.3 1.5 Interest cost 9.8 9.9 Actuarial gain (74.0) (10.8) Benefits paid (22.7) (23.3) Accumulated benefit obligations at end of year $ 251.2 $ 336.8 Plan assets: Beginning of year $ 353.5 $ 360.4 Actual return on plan assets (79.0) 16.4 Benefits paid (22.7) (23.3) Fair value of plan assets at end of year $ 251.8 $ 353.5 Accrued benefit cost at end of year: Funded status $ 0.6 $ 16.8 Recognized on balance sheet: Other noncurrent assets $ 0.6 $ 16.8 Recognized in accumulated other comprehensive income (loss), before tax: Net actuarial loss 78.7 59.9 $ 78.7 $ 59.9
Schedule of Pension and Other Postretirement Benefits Activity in Accumulated Other Comprehensive Income (Loss) [Table Text Block]	lan activity in accumulated other comprehensive loss, before tax, in 2022 is presented below, in millions. Balance at beginning of year $ 59.9 Actuarial loss 20.5 Prior year actuarial loss amortization to net periodic cost (1.7) Balance at end of year $ 78.7
Schedule of Assumptions Used	A summary of key assumptions for the valuations of our Pension Plan is as follows: September 30, 2022 2021 2020 Weighted average used to determine benefit obligations: Discount rate 5.79 % 3.01 % 2.84 % Weighted average used to determine net periodic cost: Discount rate 3.01 % 2.84 % 3.26 % Expected return on plan assets 4.50 % 4.50 % 5.00 %
Schedule of Strategic Allocation of Plan Assets [Table Text Block]	trategic asset allocations, tactical range at September 30, 2022 and actual asset allocations are as follows: Strategic asset allocation Actual asset allocations at September 30, Tactical range 2022 2021 2020 Fixed income investments 70 % 65 % - 70 % 70 % 70 % 78 % Equity investments 30 25 % - 30 % 29 29 21 Cash — 0 % - 5 % 1 1 1 100 % 100 % 100 % 100 %
Schedule of Allocation of Plan Assets	The assets of the Plan by level within the fair value hierarchy are as follows: September 30, 2022 Level 1 Level 2 Total (in millions) Fixed income $ 125.2 $ 50.1 $ 175.3 Equity: Large cap index funds 37.2 — 37.2 International stocks: International funds 37.4 — 37.4 Total equity 74.6 — 74.6 Cash and cash equivalents 1.9 — 1.9 $ 201.7 $ 50.1 $ 251.8 September 30, 2021 Level 1 Level 2 Total (in millions) Fixed income $ 176.7 $ 70.3 $ 247.0 Equity: Large cap index funds 52.1 — 52.1 International stocks: International funds 52.5 — 52.5 Total equity 104.6 — 104.6 Cash and cash equivalents 1.9 — 1.9 $ 283.2 $ 70.3 $ 353.5
Schedule of Expected Benefit Payments	Our estimated future pension benefit payments are presented below (in millions): 2023 $ 23.3 2024 23.1 2025 22.8 2026 22.4 2027 21.9 2028-2032 $ 100.7

Capital Stock (Tables)

Capital Stock (Tables)	12 Months Ended
	Sep. 30, 2022
Common Stock, Number of Shares, Par Value and Other Disclosure [Abstract]
Schedule of Common Stock Outstanding Roll Forward [Table Text Block]	Common stock share activity is presented below. Shares outstanding at September 30, 2019 157,462,140 Vesting of restricted stock units, net of shares withheld for taxes 242,112 Exercise of stock options 534,291 Exercise of employee stock purchase plan instruments 182,971 Settlement of performance-based restricted stock units, net of shares withheld for taxes 61,610 Stock repurchased under buyback program (418,374) Shares outstanding at September 30, 2020 158,064,750 Vesting of restricted stock units, net of shares withheld for taxes 182,024 Exercise of stock options 151,399 Exercise of employee stock purchase plan instruments 146,135 Settlement of performance-based restricted stock units, net of shares withheld for taxes 62,396 Stock repurchased under buyback program (651,271) Shares outstanding at September 30, 2021 157,955,433 Vesting of restricted stock units, net of shares withheld for taxes 195,156 Exercise of stock options 36,731 Exercise of employee stock purchase plan instruments 150,909 Settlement of performance-based restricted stock units, net of shares withheld for taxes 160,163 Stock repurchased under buyback program (2,654,254) Shares outstanding at September 30, 2022 155,844,138 The Company has authorized 20.0 million shares of $0.01 par value preferred stock. The preferred stock may be issued in one or more series and with such designations and preferences for each series as shall be stated in the resolutions providing for the designation and issue of each such series adopted by the Board of Directors of the Company. The Board of Directors is authorized by the Company's articles of incorporation to determine the voting, dividend, redemption and liquidation preferences pertaining to each such series. No shares of preferred stock have been issued by the Company as of September 30, 2022.

Stock-based Compensation Plans

Stock-based Compensation Plans (Tables)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Share-Based Payment Arrangement [Abstract]
Share-based Payment Arrangement, Expensed and Capitalized, Amount [Table Text Block]	The effect of stock-based compensation on our consolidated statements of operations is presented below. Such amounts are included within selling, general, and administrative costs. 2022 2021 2020 (in millions, except per share data) Decrease in operating income $ 9.9 $ 11.0 $ 7.2 Decrease in net income 7.6 8.2 5.5 Decrease in earnings per basic share 0.05 0.05 0.03 Decrease in earnings per diluted share 0.05 0.05 0.03
Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity	Restricted stock unit activity under the 2006 Plan is summarized below. Restricted stock units Weighted Weighted Aggregate Outstanding at September 30, 2019 437,022 $ 11.31 0.9 Granted 301,979 11.55 Vested (295,241) 11.40 $ 3.4 Cancelled (35,254) 11.48 Outstanding at September 30, 2020 408,506 11.41 0.9 Granted 220,795 12.29 Vested (228,121) 11.62 $ 2.8 Cancelled (5,083) 11.41 Outstanding at September 30, 2021 396,097 11.78 0.8 Granted 223,379 13.41 Vested (251,981) 11.81 $ 2.8 Cancelled (8,763) 11.87 Outstanding at September 30, 2022 358,732 $ 12.77 0.7
Schedule of Nonvested Performance-based Units Activity [Table Text Block]	Stock-settled PRSUs activity under the 2006 Plan is summarized below. Award date Settlement year Performance period Grant date per unit fair value Units Units forfeited Net units Performance factor Shares November 29, 2016 2020 2017 $ 13.26 59,285 (5,279) 54,006 1.000 54,006 2018 $ 12.50 59,286 (39,910) 19,376 1.357 26,294 2019 $ 10.53 59,290 (39,909) 19,381 0.645 12,501 January 23, 2017 2020 2017 $ 13.15 19,012 — 19,012 1.000 19,012 2018 $ 12.50 19,011 — 19,011 1.357 25,798 2019 $ 10.53 19,011 — 19,011 0.645 12,263 November 28, 2017 2021 2018 $ 12.50 57,092 — 57,092 1.357 77,474 2019 $ 10.53 57,092 (4,793) 52,299 0.645 33,733 2020 $ 11.26 57,104 (21,679) 35,425 0.909 32,202 November 27, 2018 2022 2019 $ 10.53 110,954 (8,751) 102,203 0.645 65,921 2020 $ 11.26 110,954 (13,182) 97,772 0.909 88,875 2021 $ 11.86 110,967 (28,478) 82,489 1.161 95,770 December 3, 2019 2023 2020 $ 11.26 69,988 (2,391) 67,597 0.909 61,446 2021 $ 11.86 69,989 (9,614) 60,375 1.161 70,096 2022 $ 13.81 69,988 (9,614) 60,374 0.700 42,262
Schedule of Share-based Compensation. Options	Stock option activity under the 2006 Plan is summarized below. Options Weighted Weighted Aggregate Outstanding at September 30, 2019 862,390 $ 4.89 2.0 $ 5.5 Exercised (534,291) 4.15 3.3 Cancelled — — Outstanding at September 30, 2020 328,099 $ 6.11 2.3 $ 1.4 Granted 431,520 11.86 Exercised (151,399) 4.09 1.7 Cancelled (8,421) — Outstanding at September 30, 2021 599,799 $ 10.67 7.8 $ 2.7 Granted 457,482 13.64 Exercised (36,731) 5.67 0.2 Cancelled (7,257) — Outstanding at September 30, 2022 1,013,293 $ 12.19 7.7 $ 0.3 Exercisable at September 30, 2022 278,569 $ 10.12 4.8 $ 0.3
Share-based Payment Arrangement, Option, Exercise Price Range [Table Text Block]		The ranges of exercise prices for stock options outstanding at September 30, 2022 are summarized below. Exercise price Options Weighted Weighted Exercisable options Weighted $ 5.00 - $ 9.99 139,969 8.40 1.4 139,969 8.40 $10.00 - $14.99 873,324 $ 12.79 8.7 138,600 $ 11.86 1,013,293 $ 12.19 7.7 278,569 $ 10.12
Schedule of Share-based Compensation, Phantom Award, Activity	Phantom Plan activity is summarized below. Phantom Weighted Weighted Aggregate Outstanding at September 30, 2019 256,154 $ 11.61 0.9 Granted 188,973 11.26 Vested (118,908) $ 1.3 Cancelled (11,744) 11.23 Outstanding at September 30, 2020 314,475 11.16 0.9 Granted 185,808 11.91 Vested (131,182) $ 1.6 Cancelled (24,257) 11.30 Outstanding at September 30, 2021 344,844 11.51 0.9 Granted 203,834 13.60 Vested (162,969) $ 1.6 Cancelled (46,578) 12.39 Outstanding at September 30, 2022 339,131 $ 12.74 1.1
Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	The assumptions used to determine the grant date fair value are indicated below for grants issued during our 2022 fiscal year. November 30, 2021 Variables used in determining grant date fair value: Dividend yield 1.62% Risk-free rate 1.33% Expected term (in years) 6.0

Segment Information (Tables)

Segment Information (Tables)	12 Months Ended
	Sep. 30, 2022
Segment Reporting [Abstract]
Schedules of Concentration of Risk, by Risk Factor [Table Text Block]	The Company has two significant customers that comprise greater than 10% of our gross sales. One customer comprised 21%, 18%, and 17% of consolidated revenues for the fiscal years ended September 30, 2022, 2021, and 2020, respectively. The Company has outstanding accounts receivable from this customer of $52.1 million and $48.1 million as of September 30, 2022 and 2021, respectively. Another customer comprised 20%, 19%, and 17% of consolidated revenues for the fiscal years ended September 30, 2022, 2021, and 2020, respectively. The Company has outstanding accounts receivable from this customer of $38.6 million and $32.1 million as of September 30, 2022 and 2021, respectively. The Company reports revenue for these customers in both reportable segments, Water Flow Sol utions and Water Management Solutions.
Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas	Geographical area information is presented below. United States Israel Other Total (in millions) Property, plant and equipment, net: September 30, 2022 $ 284.9 $ 12.6 $ 4.1 $ 301.6 September 30, 2021 263.9 13.8 5.7 283.4 Year ended September 30, 2022 2021 2020 (in millions) Water Flow Solutions disaggregated net revenues: Central $ 190.9 $ 155.1 $ 133.6 Northeast 125.3 110.4 95.1 Southeast 154.3 125.7 108.3 West 182.8 172.4 148.5 United States $ 653.3 $ 563.6 $ 485.5 Canada 55.0 45.7 39.4 Other international locations 5.8 8.5 7.3 $ 714.1 $ 617.8 $ 532.2 Water Management Solutions disaggregated net revenues: Central $ 142.9 $ 125.6 $ 107.3 Northeast 115.1 100.2 112.1 Southeast 109.4 106.5 76.3 West 102.9 99.1 81.8 United States $ 470.3 $ 431.4 $ 377.5 Canada 39.2 38.1 33.4 Other international locations 23.8 23.7 21.0 $ 533.3 $ 493.2 $ 431.9
Schedule Of Selected Supplemental Balance Sheet Information	Summarized financial information for our segments is presented below. Water Flow Water Management Corporate Total (in millions) Net revenue: 2022 $ 714.1 $ 533.3 $ — $ 1,247.4 2021 617.8 493.2 — 1,111.0 2020 532.2 431.9 — 964.1 Operating income (loss): 2022 $ 118.3 $ 48.7 $ (55.4) $ 111.6 2021 120.9 70.3 (59.5) 131.7 2020 104.9 68.7 (56.8) 116.8 Depreciation and amortization: 2022 $ 30.0 $ 30.3 $ 0.2 $ 60.5 2021 30.5 28.9 0.2 59.6 2020 28.9 28.7 0.2 57.8 Strategic reorganization and other charges: 2022 $ 0.2 $ 0.4 $ 6.6 $ 7.2 2021 0.1 (0.4) 8.3 8.0 2020 — 0.7 12.3 13.0 Capital expenditures: 2022 $ 43.4 $ 11.3 $ — $ 54.7 2021 51.0 11.6 0.1 62.7 2020 57.3 10.1 0.3 67.7 Intangible assets, net and goodwill September 30, 2022 $ 302.6 $ 157.2 $ — $ 459.8 September 30, 2021 324.1 183.5 — 507.6 Inventories, net: September 30, 2022 $ 160.5 $ 118.2 $ — 278.7 September 30, 2021 $ 104.5 $ 80.2 $ — 184.7

Leases, Codification Topic 842

Leases, Codification Topic 842 (Tables)	12 Months Ended
	Sep. 30, 2022
Leases [Abstract]
Lease, Cost	The components of lease cost are presented below. Year ended September 30, 2022 2021 2020 (in millions) Operating lease cost $ 5.8 $ 6.1 $ 6.3 Finance lease cost 1.3 1.2 1.3 Total lease expense $ 7.1 $ 7.3 $ 7.6
Supplemental Balance Sheet - Leases	Supplemental information regarding our lease assets and liabilities is below. September 30, 2022 2021 (in millions) Right-of-use assets: Operating leases Other noncurrent assets $ 26.0 $ 27.1 Finance leases Plant, property and equipment 1.4 2.2 Total right-of-use assets $ 27.4 $ 29.3 Lease liabilities: Operating leases - current Other current liabilities $ 4.4 $ 4.0 Operating leases - noncurrent Other noncurrent liabilities 22.4 24.6 Finance leases - current Current portion of long-term debt 0.8 1.0 Finance leases - noncurrent Long-term debt 0.8 1.2 Total lease liabilities $ 28.4 $ 30.8
Supplemental Information - Leases	Supplemental information related to lease terms and discount rates are presented below. Year ended September 30, 2022 2021 Weighted-average remaining lease term (years): Operating leases 6.67 7.82 Finance leases 2.15 2.53 Weighted-average interest rate: Operating leases 5.48 % 5.36 % Finance leases 3.64 % 4.24 %
Lease Maturity Schedule	Total lease liabilities at September 30, 2022 have scheduled maturities as follows: Operating Leases Finance Leases (in millions) 2023 $ 5.9 $ 0.9 2024 5.7 0.5 2025 5.1 0.2 2026 4.7 0.1 2027 3.9 — Thereafter 7.3 — Total lease payments 32.6 1.7 Less: imputed interest (5.8) (0.1) Present value of lease liabilities $ 26.8 $ 1.6
ScheduleOfCashFlowSupplementalDisclosures - Leases	Supplemental cash flow information related to leases are presented below, in millions. Year ended September 30, 2022 2021 Operating cash used for operating leases $ 5.8 $ 6.1 Financing cash used for finance leases $ 1.3 $ 1.2

Other Income and Expenses (Tabl

Other Income and Expenses (Tables)	12 Months Ended
	Sep. 30, 2022
Other Income and Expenses [Abstract]
Restructuring and Related Costs	Activity in accrued restructuring, reported as part of other current liabilities, is presented below. 2022 2021 2020 (in millions) Beginning balance $ 3.1 $ 2.8 $ 1.7 Expenses incurred $ 7.2 $ 5.4 $ 4.8 Amounts paid $ (7.0) $ (5.1) $ (3.7) Ending balance $ 3.3 $ 3.1 $ 2.8

Organization (Details)

Organization (Details) $ in Millions			12 Months Ended
	Oct. 03, 2019	Jul. 31, 2014	Sep. 30, 2022 USD ($) business_segments	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization			Organization Mueller Water Products, Inc., a Delaware corporation, together with its consolidated subsidiaries, operates in two business segments: Water Flow Solutions and Water Management Solutions. These segments are based on a management reorganization that became effective October 1, 2021; prior period information has been recast to conform to the current presentation. Water Flow Solutions’ product portfolio includes iron gate valves, specialty valves and service brass products. Water Management Solutions’ product and service portfolio includes fire hydrants, repair and installation, natural gas, metering, leak detection, pressure control and monitoring services. The “Company,” “we,” “us” or “our” refer to Mueller Water Products, Inc. and its subsidiaries. With regard to the Company’s segments, “we,” “us” or “our” may also refer to the segment being discussed. We have approximately 3,600 employees globally, of which 64% of our hourly workers are covered by collective bargaining agreements. In July 2014, we acquired a 49% ownership in an industrial valve joint-venture for $1.7 million. As a result of substantive control features in the joint-venture agreement, all of the joint venture’s assets, liabilities and results of operations were included in our consolidated financial statements. The noncontrolling interest portion was included in selling, general and administrative expenses. Noncontrolling interest was recorded at its carrying value, which approximated fair value. We acquired the remaining 51% noncontrolling interest on October 3, 2019. On December 3, 2018, we completed our acquisition of Krausz Industries Development Ltd. and subsidiaries (“Krausz”). During our 2020 and 2019 fiscal years, we included the financial statements of Krausz on a one-month lag. During the three months ended March 31, 2021, we aligned the consolidation of the financial statements of Krausz in the Company’s consolidated financial statements, eliminating the previous inclusion of Krausz financial statements with a one-month reporting lag. In accordance with applicable accounting literature, the elimination of the one-month reporting lag is considered to be a change in accounting principle. We believe this change in accounting principle is preferable as the financial statements of all of our subsidiaries are now reported on the same basis, providing the most current information available. The effect of the elimination of the reporting lag during the year ended September 30, 2021 resulted in an increase of $6.0 million to net sales and an increase of $1.4 million to operating income. We concluded that the effect of this change is not material to the balance sheets, statements of operations, statements of cash flows, net income and earnings per share and therefore have not retrospectively applied this change. On June 14, 2021, we acquired all the outstanding capital stock of i2O Water Ltd (“i2O”) a provider of pressure management solutions to more than 100 water companies in 45 countries. The consolidated balance sheet at September 30, 2021 includes the preliminary estimated fair values of the net assets of i2O. The accounting for this business combination became final during the three months ended March 31, 2022. The results of i2O’s operations and cash flows for the period subsequent to the acquisition are included in the consolidated statement of operations and consolidated statement of cash flows, respectively. Refer to Note 5. for additional disclosures related to the acquisition. Our consolidated financial statements are prepared in conformity with accounting principles generally accepted in the United States of America (“GAAP”), which require us to make certain estimates and assumptions that affect the reported amounts of assets, liabilities, sales and expenses and the disclosure of contingent assets and liabilities for the reporting periods. Actual results could differ from those estimates. All significant intercompany balances and transactions have been eliminated. Certain reclassifications have been made to previously reported amounts to conform to the current presentation. Unless the context indicates otherwise, whenever we refer to a particular year, we mean our fiscal year ended or ending September 30 in that particular calendar year. New Markets Tax Credit Program On December 22, 2020, we entered into a financing transaction with Wells Fargo Community Investment Holdings, LLC (“Wells Fargo”) related to our brass foundry construction project in Decatur, Illinois under a qualified New Markets Tax Credit program (“NMTC”). The NMTC is a federal program intended to encourage capital investment in qualified lower income communities. Under the NMTC, investors claim federal income tax credits over a period of seven years in connection with qualified investments in the equity of community development entities (“CDE”s), which are privately managed investment institutions that are certified to make qualified low-income community investments, such as in our foundry project. Under the NMTC, Wells Fargo contributed capital of $4.8 million to an investment fund and we loaned $12.2 million to the fund. Wells Fargo is entitled to the associated tax credits, which are subject to 100% recapture if we do not comply with various regulations and contractual provisions surrounding the foundry project. We have indemnified Wells Fargo for any loss or recapture of tax credits related to the transaction until the seven-year period elapses. We do not anticipate any credit recaptures will be required in connection with this arrangement. The investment fund contributed $16.5 million cash for a 99.99% stake in a joint venture (“Sub-CDE”) with a CDE. The Sub-CDE then loaned $16.2 million to us, with the use of the loan proceeds restricted to foundry project expenditures. This transaction also includes a put/call provision under which we may be obligated or entitled to repurchase Wells Fargo’s interest in the investment fund. We believe that Wells Fargo will exercise its put option in December 2027 for nominal consideration, resulting in our becoming the sole owner of the investment fund, cancelling the related loans, and recognizing an estimated gain of $3.9 million. We determined that the investment fund and the Sub-CDE are variable interest entities (“VIEs”) and that we are the primary beneficiary of the VIEs. The ongoing activities of the VIEs, namely collecting and remitting interest and fees and administering NMTC compliance, were contemplated in the initial design of the transaction and are not expected to significantly affect economic performance throughout the life of the VIEs. Additionally, we are obligated to deliver tax benefits and provide various other guarantees to Wells Fargo and to absorb the losses of the VIEs. Wells Fargo does not have a material interest in the underling economics of the project. Consequently, we have included the financial statements of the VIEs in our consolidated financial statements. Intercompany transactions between us and the VIEs have been eliminated in consolidation. Wells Fargo’s contribution to the investment fund is consolidated in our financial statements as an Other noncurrent liability as a result of its redemption features. Direct costs associated with Wells Fargo’s capital contribution have been netted against the recorded proceeds, resulting in a net cash contribution of $3.9 million. Other direct costs associated with the transaction were capitalized and will be recognized as interest expense over the seven-year tax credit period. Incremental costs to maintain the structure during the compliance period are expensed as incurred.
Number of Reportable Segments | business_segments			2
Variable Interest Entity, Qualitative or Quantitative Information, Ownership Percentage	51%	49%
Payments to Acquire Interest in Joint Venture				$ 1.7
Proceeds from Other Equity			$ 0	$ 3.9	$ 0
Proceeds From Other Equity, Gross Amount			4.8
Intercompany Loan Related to NMTC			12.2
Investment Fund Contribution For NMTC			16.5
Sub CDE Loan From NMTC			$ 16.2

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Schedule of Allowance for Doubtful Receivables) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Balance at beginning of year	$ 3.5	$ 2.5	$ 1.5
Accounts Receivable, Credit Loss Expense (Reversal)	2.5	1.1	1.1
Balances written off, net of recoveries	(0.4)	(0.1)	(0.1)
Balance at end of year	5.6	3.5	$ 2.5
Accounts Receivable, Allowance for Credit Loss, Current	$ (5.6)	$ (3.5)

Summary of Significant Accoun_5

Summary of Significant Accounting Policies (Schedule of Reserves for Excess and Obsolete Inventory) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
SEC Schedule, 12-09, Valuation and Qualifying Accounts Disclosure [Line Items]
Balance at beginning of year	$ 14.8	$ 11.7	$ 7.5
Provision charged to expense	(1.8)	(5.9)	(4.7)
Inventory Valuation Allowances and Reserves, Deduction	(1.4)	(3.6)	(0.7)
SEC Schedule, 12-09, Valuation Allowances and Reserves, Increase (Decrease) Adjustment	1.3	0.8	0.2
Balance at end of year	$ 16.5	$ 14.8	$ 11.7

Summary of Significant Accoun_6

Summary of Significant Accounting Policies (Schedule of Product Warranty Liability) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Accounting Policies [Abstract]
Balance at end of year	$ 10.7	$ 9.7	$ 14.4	$ 17.1
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance at beginning of year	6.7
Product Warranty Expense	9.5	3.5	2.6
Warranty payments	(8.5)	(8.2)	$ (5.3)
Balance at end of year	$ 6.5	$ 6.7

Summary of Significant Accoun_7

Summary of Significant Accounting Policies (Narrative) (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Product Warranty Expense	$ 9,500,000	$ 3,500,000	$ 2,600,000
Asset Retirement Obligation	3,600,000	3,800,000
Exposure to Workers Compensation Claims, Per Incident	800,000
Workers' Compensation Liability	$ 11,100,000	$ 10,500,000
Income Tax Benefit, Likelihood of Realization Threshold	50%
Debt Issuance Costs, Net	$ 5,600,000
Minimum [Member]
Finite-Lived Tangible Asset, Useful Life, Maximum		3 years
Maximum [Member]
Finite-Lived Tangible Asset, Useful Life, Maximum		10 years
Land Improvements [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life, Minimum	10 years
Land Improvements [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life, Minimum	20 years
Building [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life, Minimum	10 years
Building [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life, Minimum	40 years
Machinery and Equipment [Member] | Minimum [Member]
Property, Plant and Equipment, Useful Life, Minimum	3 years
Machinery and Equipment [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life, Minimum	15 years
Software and Software Development Costs [Member] | Maximum [Member]
Property, Plant and Equipment, Useful Life, Minimum	6 years
U.S. Pipe [Member] | Maximum [Member]
Discontinued Operations, Receivable from Buyer of Discontinued Operation	$ 5,900,000	$ 3,500,000
Revolving Credit Facility [Member]
Debt Issuance Costs, Net	700,000
Secured Debt [Member]
Debt Issuance Costs, Net	4,700,000	$ 5,300,000
Unsecured Debt [Member]
Debt Issuance Costs, Net	4,600,000
Debt
Debt Issuance Costs, Net	$ 300,000

Revenue from Contracts with C_2

Revenue from Contracts with Customers Components of Trade Receivables (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans, Notes, Trade and Other Receivables Disclosure [Text Block]	The table below represents the balances of our customer receivables and deferred revenues. September 30, 2022 2021 (in millions) Billed receivables $ 230.5 $ 213.4 Unbilled receivables 3.1 2.3 Gross customer receivables $ 233.6 $ 215.7 Allowance for credit losses (5.6) (3.5) Receivables, net $ 228.0 $ 212.2 Deferred revenues $ 8.1 $ 5.4
Billed receivables	$ 230.5	$ 213.4
Unbilled receivables	3.1	2.3
Total customer receivables	233.6	215.7
Deferred revenues	$ 8.1	$ 5.4

Revenue from Contracts with C_3

Revenue from Contracts with Customers Narrative (Details)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2020
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue by Recognition Timing	2%	1%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Percent of Revenue by Recognition Timing	98%	99%

Business Combination Narrative

Business Combination Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Repayment of Krausz debt	$ (0.7)	$ (0.4)	$ (0.4)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets	0.9
Inventories	0.6
Receivables	0.5
Goodwill	12.1
Accounts payable and other current liabilities	(0.8)
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities	(1.3)
Consideration paid	19.5
Payments for Previous Acquisition	19.5
Customer-Related Intangible Assets [Member]
Business Acquisition [Line Items]
Patents	2.1
Noncompete Agreements
Business Acquisition [Line Items]
Patents	0.1
Developed Technology Rights
Business Acquisition [Line Items]
Patents	3.5
Trademarks and Trade Names [Member]
Business Acquisition [Line Items]
Tradenames	$ 1.8

Business Combination Schedule o

Business Combination Schedule of Business Acquisitions, by Acquisition (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Assets acquired:
Receivables	$ 0.5
Inventories	0.6
Goodwill	98.6	$ 115.1	$ 99.8
Goodwill	12.1
Accounts payable and other current liabilities	(0.8)
Consideration paid	19.5
Repayment of Krausz debt	0.7	$ 0.4	$ 0.4
Customer-Related Intangible Assets [Member]
Assets acquired:
Patents	$ 2.1

Identifiable Intangible Asset_2

Identifiable Intangible Assets Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Amortization	$ 28.5	$ 28.2	$ 28.2
Goodwill	$ 98.6	115.1	99.8
Software and Software Development Costs [Member]
Finite-Lived Intangible Asset, Useful Life	6 years
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life	3 years 7 months 6 days
Amortization	$ 2.9
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	3.1
Finite-Lived Intangible Assets, Amortization Expense, Year Two	2.5
Finite-Lived Intangible Assets, Amortization Expense, Year Three	1.5
Finite-Lived Intangible Assets, Amortization Expense, Year Four	0.9
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 0.5
Customer Relationships [Member]
Finite-Lived Intangible Asset, Useful Life	3 years 3 months 18 days
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Asset, Useful Life	8 years 6 months
Business Combination-Related Identifiable Intangible [Member]
Amortization	$ 25.5	$ 25.2	$ 24.9
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	25.1
Finite-Lived Intangible Assets, Amortization Expense, Year Two	24.6
Finite-Lived Intangible Assets, Amortization Expense, Year Three	5.6
Finite-Lived Intangible Assets, Amortization Expense, Year Four	4.9
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 4.7

Identifiable Intangible Asset_3

Identifiable Intangible Assets Schedule of Intangible Assets and Goodwill (Details) - USD ($)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Indefinite-lived intangible assets:
Goodwill	$ 98,600,000	$ 115,100,000	$ 99,800,000
Intangible Assets, Gross, (Including Goodwill)	764,200,000	770,300,000
Accumulated amortization:
Intangible Assets, Net (Excluding Goodwill)	361,200,000	392,500,000
Goodwill, Acquired During Period	12
Indefinite-lived Intangible Assets, Foreign Currency Translation Gain (Loss)	(9,700,000)	3,200,000
i2O
Accumulated amortization:
Goodwill, Acquired During Period		12,100,000
Business Combination-Related Identifiable Intangible [Member]
Accumulated amortization:
Accumulated Amortization	411,700,000	387,800,000
Net book value	352,500,000	382,500,000
Trademarks and Trade Names [Member]
Indefinite-lived intangible assets:
Trade names and trademarks	272,700,000	273,800,000
Software and Software Development Costs [Member]
Capitalized external-use software:
Capitalized Computer Software, Gross	35,500,000	34,100,000
Accumulated amortization	26,800,000	24,100,000
Net book value	8,700,000	10,000,000
Technology-Based Intangible Assets [Member]
Finite-lived intangible assets:
Technology	119,900,000	123,500,000
Accumulated amortization:
Accumulated Amortization	89,500,000	85,800,000
Customer Relationships [Member]
Finite-lived intangible assets:
Customer relationships and other	371,600,000	373,000,000
Accumulated amortization:
Accumulated Amortization	$ 322,200,000	$ 302,000,000

Income Taxes (Narrative) (Detai

Income Taxes (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	$ 0.7	$ 0.6
Income tax expense (benefit)	22	24.5	$ 22.1
Deferred Tax Assets, Tax Credit Carryforwards, Foreign		4.5
Unrecognized Tax Benefits	4.7	4.8	$ 4.5
Unrecognized Tax Benefits, Decrease Resulting from Current Period Tax Positions	(0.4)	0
Unrecognized Tax Benefits, Decrease Resulting from Foreign Currency Translation	(0.1)	0
transition tax liability	$ 4.1	$ 4.7

Income Taxes (Income before Inc

Income Taxes (Income before Income Tax, Domestic and Foreign) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Loss before income taxes, U.S.	$ 81.6	$ 94	$ 89.7
Loss before income taxes, Non-U.S.	17	0.9	4.4
Net Income Before Income Tax	$ 98.6	$ 94.9	$ 94.1

Income Taxes (Components of Inc

Income Taxes (Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Current:
Current Federal Tax Expense (Benefit)	$ 19.5	$ 21.9	$ 10.9
Current State and Local Tax Expense (Benefit)	4.3	6.3	2.7
Current Foreign Tax Expense (Benefit)	1.7	1.6	1.3
Current Income Tax Expense (Benefit)	25.5	29.8	14.9
Deferred:
Deferred Federal Income Tax Expense (Benefit)	(3.4)	(4.7)	5.6
Deferred State and Local Income Tax Expense (Benefit)	(0.9)	(1.3)	2
Deferred Foreign Income Tax Expense (Benefit)	0.8	0.7	(0.4)
Deferred Income Tax Expense (Benefit)	(3.5)	(5.3)	7.2
Income tax expense (benefit)	$ 22	$ 24.5	$ 22.1

Income Taxes (Disposal Groups,

Income Taxes (Disposal Groups, including Discontinued Operations) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Income tax expense (benefit)	$ 22	$ 24.5	$ 22.1

Income Taxes (Reconciliation of

Income Taxes (Reconciliation of Statutory Taxes to Effective Taxes) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Income Tax Disclosure [Abstract]
Tax at U.S. federal statutory income tax rate of 35%	$ 20.7	$ 19.9	$ 19.8
Adjustments to reconcile to income tax expense (benefit):
Federal Valuation Allowance	1	(0.4)	0.1
State income taxes, net of federal benefit	2.6	3.1	3.3
Uncertain tax positions	0	0.3	1
Basis difference in foreign investment	0.1	1.5	0.1
Excess tax benefits related to stock compensation	(0.1)	(0.2)	(0.5)
Tax Credits	(2.3)	(1.6)	(1.8)
Other nondeductible expenses	0.8	0.5	0.4
Foreign income taxes	(1.5)	(1.7)	(0.5)
Nondeductible compensation	0.9	0.6	0.6
Other income tax	(0.2)	2.5	(0.4)
Income tax expense (benefit)	$ 22	$ 24.5	$ 22.1

Income Taxes (Deferred Tax Asse

Income Taxes (Deferred Tax Assets and Liabilities) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Deferred income tax assets:
Accrued expenses	$ 10.5	$ 12.7
Deferred Tax Assets Leasing Liabilities	8.1	8.2
Inventory reserves	7	6.1
State net operating losses	2.1	2.8
Federal net operating losses and credit carryovers	12.9	14.8
Pension and other postretirement benefits	0.1	0
Stock-based compensation	4.1	3.8
All other	2.3	2.9
Deferred income tax assets	47.1	51.3
Valuation allowance	(13.2)	(13.6)
Total deferred income tax assets	33.9	37.7
Deferred income tax liabilities:
Identifiable intangible assets	(77.7)	(86.3)
Pension and other postretirement benefits	6.2	6.8
Pension	0	3.9
Deferred Tax Liabilities, Leasing Arrangements	7.4	7.6
Other	(0.5)	(0.5)
Total deferred income tax liabilities	120.2	132.5
Net deferred income tax liabilities	86.3	94.8
Deferred Tax Liabilities, Gross, Noncurrent	86.3	95.1
Deferred Tax Liabilities, Property, Plant and Equipment	$ 28.4	$ 27.4

Income Taxes (Gross Unrecognize

Income Taxes (Gross Unrecognized Tax Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Unrecognized Tax Benefits [Roll Forward]
Balance at beginning of year	$ 4.8	$ 4.5
Increases related to current year positions	0.7	0.6
Decreases due to lapse in statute of limitations	(0.3)	(0.3)
Balance at end of year	$ 4.7	$ 4.8

Income Taxes (Summary of Valuat

Income Taxes (Summary of Valuation Allowance) (Details) $ in Millions	Sep. 30, 2022 USD ($)
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of year	$ 13.6
Balance at end of year	$ 13.2

Borrowing Arrangements (Narrati

Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Debt Instrument [Line Items]
Outstanding Letter Of Credit Accrued Fees And Expenses	$ 0.2
Outstanding Letter Of Credit Accrued Fees And Expenses	0.2
Long-Term Debt, Maturity, Year One	0.8
Long-Term Debt, Maturity, Year Two	0.5
Long-Term Debt, Maturity, Year Three	0.3
Long-Term Debt, Maturity, Year Four	0
CY plus 6 and more	450
Outstanding Letter of Credit	14.1
Gain (Loss) on Extinguishment of Debt	0	$ (16.7)	$ 0
Payment for Debt Extinguishment or Debt Prepayment Cost	12.4
Write off of Deferred Debt Issuance Cost	4.3
4.0% Senior Notes
Debt Instrument [Line Items]
Payments of Debt Issuance Costs	5.5
Financial Liabilities Fair Value Disclosure	382.1
Payments of Debt Issuance Costs	5.5
Financial Liabilities Fair Value Disclosure	382.1
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		175
Potential Increase In The Size Of Credit Facility	$ 150
Line of Credit Facility, Interest Rate at Period End	200%
Maximum excess availability level at which financial maintenance covenants would apply	$ 17.5
Maximum excess availability level at which financial maintenance covenants would apply, as a percentage of aggregate commitments	10%
Line of Credit Facility, Remaining Borrowing Capacity	$ 160.7
Line of Credit Facility, Remaining Borrowing Capacity	160.7
Potential Increase In The Size Of Credit Facility	$ 150
Line of Credit Facility, Maximum Borrowing Capacity		$ 175
Line of Credit Facility, Interest Rate at Period End	200%
Maximum excess availability level at which financial maintenance covenants would apply	$ 17.5
Maximum excess availability level at which financial maintenance covenants would apply, as a percentage of aggregate commitments	10%
Bonds [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage	4%	5.50%
Debt Instrument, Interest Rate, Effective Percentage	4%	5.50%
Swing Line Loans [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	$ 25
Line of Credit Facility, Maximum Borrowing Capacity	25
Letter Of Credit [Member]
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	60
Line of Credit Facility, Maximum Borrowing Capacity	$ 60
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	200%
Debt Instrument, Basis Spread on Variable Rate	200%
London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	225%
Debt Instrument, Basis Spread on Variable Rate	225%
Base Rate [Member] | Minimum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	100%
Debt Instrument, Basis Spread on Variable Rate	100%
Base Rate [Member] | Maximum [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	125%
Debt Instrument, Basis Spread on Variable Rate	125%

Borrowing Arrangements (Compone

Borrowing Arrangements (Components Of Long-Term Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Unsecured Debt	$ 451.6	$ 452.2
Debt Issuance Costs, Net	(5.6)
Current portion of long-term debt	(0.8)	(1)
Long-term debt, excluding current maturities	446.1	445.9
Revolving Credit Facility [Member]
Debt Issuance Costs, Net	(0.7)
Secured Debt [Member]
Debt Issuance Costs, Net	(4.7)	(5.3)
Other [Member]
Unsecured Debt	1.6	2.2
Unsecured Debt [Member]
Debt Issuance Costs, Net	(4.6)
Unsecured Debt [Member] | 4.0% Senior Notes
Unsecured Debt	450
5.5% Senior Notes	$ 450	450
Unsecured Debt [Member] | 5.5% Senior Notes
Unsecured Debt		$ 450

Derivative Financial Instrume_2

Derivative Financial Instruments (Details) $ in Millions	Sep. 30, 2021 USD ($)
Foreign Exchange Contract [Member]
Derivative [Line Items]
Derivative Liability, Noncurrent	$ 1.1

Retirement Plans (Narrative) (D

Retirement Plans (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)		$ (1.7)	$ (2.5)	$ (2.8)
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		5.79%	3.01%	2.84%
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		100%
Discount rate		3.01%	2.84%	3.26%
Defined Contribution Plan, Cost		$ 7.3	$ 5.9	$ 5.3
Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon		1,000%
Maximum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon		1,500%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		30%
Equity Securities [Member] | Minimum [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage		25%
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	$ (3.7)

Retirement Plans (Net Periodic

Retirement Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Service cost	$ 1.3	$ 1.5	$ 1.5
Interest cost	9.8	9.9	11.2
Expected return on plan assets	(15.4)	(15.7)	(16.9)
Amortization of net loss (gain)	1.7	2.5	2.8
Other	0	0	(0.1)
Defined Benefit Plan, Net Periodic Benefit Cost other than Service Cost	(3.9)	(3.3)	(3)
Defined Benefit Plan, Net Periodic Benefit Cost (Credit)	(2.6)	(1.8)	$ (1.5)
Pension Plan, Defined Benefit [Member]
Service cost	1.3	1.5
Interest cost	$ 9.8	$ 9.9

Retirement Plans (Amounts Recog

Retirement Plans (Amounts Recognized for Pension and Other Postretirement Benefit Plans) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Projected benefit obligations:
Service cost	$ 1.3	$ 1.5	$ 1.5
Interest cost	9.8	9.9	11.2
Plan assets:
Beginning of year	353.5
End of year	251.8	353.5
Recognized on balance sheet:
Pension asset	0.6	16.8
Pension Plan, Defined Benefit [Member]
Projected benefit obligations:
Beginning of year	336.8	359.5
Service cost	1.3	1.5
Interest cost	9.8	9.9
Actuarial loss (gain)	(74)	(10.8)
Benefits paid	(22.7)	(23.3)
End of year		336.8	359.5
Accumulated benefit obligation at end of year	251.2	336.8
Plan assets:
Beginning of year	353.5	360.4
Actual return on plan assets	(79)	16.4
Benefits paid	(22.7)	(23.3)
End of year	251.8	353.5	$ 360.4
Accrued benefit cost at end of year:
Unfunded status	0.6	16.8
Recognized on balance sheet:
Pension asset	0.6	16.8
Recognized in accumulated other comprehensive loss, before tax:
Net actuarial loss (gain)	78.7	59.9
Recognized in accumulated other comprehensive loss, before tax	$ 78.7	$ 59.9

Retirement Plans (Pension and O

Retirement Plans (Pension and Other Postretirement Benefits Activity in Accumulated Other Comprehensive Income) (Details) - Pension Plan, Defined Benefit [Member] $ in Millions	12 Months Ended
	Sep. 30, 2022 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Balance at beginning of year	$ 59.9
Balance at beginning of year	59.9
Actuarial gain	20.5
Prior year service loss amortization to net periodic cost	(1.7)
Balance at end of year	$ 78.7

Retirement Plans (Components of

Retirement Plans (Components of Accumulated Other Comprehensive Income (Loss) Related to Pension and Other Postretirement Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)		$ 1.7	$ 2.5	$ 2.8
Pension Plan, Defined Benefit [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax		(1.7)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax		(20.5)
Defined Benefit Plan, Accumulated Other Comprehensive (Income) Loss, before Tax		$ 78.7	$ 59.9
Forecast [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	$ 3.7

Retirement Plans (Assumptions U

Retirement Plans (Assumptions Used) (Details)	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Weighted average used to determine benefit obligations:
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate	5.79%	3.01%	2.84%
Weighted average used to determine net periodic cost:
Discount rate	3.01%	2.84%	3.26%
Expected return on plan assets	4.50%	4.50%	5%
Minimum [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan Expected Return on Plan Assets Major Asset Classes Time Horizon	1,000%

Retirement Plans (Strategic All

Retirement Plans (Strategic Allocation of Plan Assets) (Details)	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	100%
Actual asset allocations
Actual plan asset allocations	100%	100%	100%
Equity Securities [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	30%
Actual asset allocations
Actual plan asset allocations	29%	29%	21%
Fixed Income Securities [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	70%
Fixed Income Funds [Member]
Actual asset allocations
Actual plan asset allocations	70%	70%	78%
Cash and Cash Equivalents [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Actual asset allocations
Actual plan asset allocations	1%	1%	1%
Minimum [Member] | Equity Securities [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	25%
Minimum [Member] | Fixed Income Funds [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	65%
Minimum [Member] | Cash and Cash Equivalents [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	0%
Maximum [Member] | Fixed Income Funds [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	70%
Maximum [Member] | Cash and Cash Equivalents [Member]
Strategic asset allocation
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	5%

Retirement Plans (Fair Value As

Retirement Plans (Fair Value Asset Allocation) (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 251.8	$ 353.5
Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	201.7	283.2
Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50.1	70.3
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	74.6	104.6
Equity Securities [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	74.6	104.6
Equity Securities [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Large Cap Growth Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		52.1
Large Cap Growth Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		52.1
Large Cap Growth Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets		0
Large Cap Index Funds [Member] [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	37.2
Large Cap Index Funds [Member] [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	37.2
Large Cap Index Funds [Member] [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0
International Stocks [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	37.4	52.5
International Stocks [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	37.4	52.5
International Stocks [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	0	0
Fixed Income Funds [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	175.3	247
Fixed Income Funds [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	125.2	176.7
Fixed Income Funds [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	50.1	70.3
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1.9	1.9
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	1.9	1.9
Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member]
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 0	$ 0

Retirement Plans (Expected Bene

Retirement Plans (Expected Benefit Payments) (Details) $ in Millions	Sep. 30, 2022 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated benefit payments, CY plus 1	$ 23.3
Estimated benefit payments, CY plus 2	23.1
Estimated benefit payments, CY plus 3	22.8
Estimated benefit payments, CY plus 4	22.4
Estimated benefit payments, CY plus 5	21.9
Estimated benefit payments, CY plus 6 and up	$ 100.7

Retirement Plans Schedule of Am

Retirement Plans Schedule of Amounts Expected to Amortize from AOCI to net income in the coming year (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)		$ (1.7)	$ (2.5)	$ (2.8)
Forecast [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Amortization of Gain (Loss)	$ (3.7)

Capital Stock (Details)

Capital Stock (Details) - $ / shares	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Outstanding Shares [Roll Forward]
Shares outstanding	157,955,433	158,064,750	157,462,140
Exercised stock options	36,731	151,399	534,291
Exercise of employee stock purchase plan	150,909	146,135	182,971
Vesting of restricted stock units, net of shares withheld for taxes	195,156	182,024	242,112
Shares outstanding	155,844,138	157,955,433	158,064,750
Stock repurchased under buyback program	(2,654,254)	(651,271)	(418,374)
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period		62,396
Preferred Stock, Shares Authorized	20
Preferred Stock, Par or Stated Value Per Share	$ 0.01
Performance Shares [Member]
Outstanding Shares [Roll Forward]
Settlement of performance-based restricted stock units, net of shares withheld for taxes	240,412,000,000	103,058,000,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period	160,163		61,610

Stock-based Compensation Plan_2

Stock-based Compensation Plans (Narrative) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019	Dec. 14, 2011
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount	790,759	578,005	267,298
Weighted-average recognition period, Compensation expense related to stock awards not yet vested	1 year 6 months
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 7.6
Number of shares authorized under a Plan					20,500,000
Shares available for future grants under a Plan	5,083,831
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period	10 years
Share-based Compensation, Expected Forfeiture Rate	2%
Phantom Share Units (PSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Settlement of performance-based restricted stock units, net of shares withheld for taxes	162,969	131,182	118,908
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	203,834	185,808	188,973
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 12.74	$ 11.51	$ 11.16	$ 11.61
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instrument Other than Option, Nonvested, Intrinsic Value	$ 10.27
Share-based compensation liability	$ 2.3
Employee Stock [Member]
Number of shares authorized under a Plan			5,800,000
Shares available for future grants under a Plan	2,103,114
Price for shares offered under ESPP, as a percentage of closing price on the first or last day of the offering period	85%
Performance Shares [Member]
Settlement of performance-based restricted stock units, net of shares withheld for taxes	240,412,000,000	103,058,000,000
Restricted Stock Units (RSUs) [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Settlement of performance-based restricted stock units, net of shares withheld for taxes	251,981	228,121	295,241
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	223,379	220,795	301,979
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value	$ 12.77	$ 11.78	$ 11.41	$ 11.31
Minimum [Member] | Performance Shares [Member]
Performance Factor	0%
Maximum [Member] | Performance Shares [Member]
Performance Factor	200%

Stock-based Compensation Plan_3

Stock-based Compensation Plans (Schedule of Share-based Compensation, Effect on Statement of Operations) (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Decrease in operating income	$ 9.9	$ 11	$ 7.2
Effect on net income or loss	$ (7.6)	$ (8.2)	$ (5.5)
Effect on earnings or loss per basic share	$ (0.05)	$ (0.05)	$ (0.03)
Effect on earnings or loss per diluted share	$ (0.05)	$ (0.05)	$ (0.03)

Stock-based Compensation Plan_4

Stock-based Compensation Plans (Schedule of Share-based Compensation, Restricted Stock Units Activity) (Details) - Restricted Stock Units (RSUs) [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
RSUs, Outstanding, Number	358,732	396,097	408,506	437,022
Outstanding, Weighted average grant date fair value per share	$ 12.77	$ 11.78	$ 11.41	$ 11.31
Outstanding, Weighted average remaining contractual term	8 months 12 days	9 months 18 days	10 months 24 days	10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	223,379	220,795	301,979
Granted, Weighted average grant date fair value per share	$ 13.41	$ 12.29	$ 11.55
Settlement of performance-based restricted stock units, net of shares withheld for taxes	251,981	228,121	295,241
RSUs, Vested in Period, Weighted Average Grant Date Fair Value	$ 11.81	$ 11.62	$ 11.40
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 2.8	$ 2.8	$ 3.4
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(8,763)	(5,083)	(35,254)
Canceled, Weighted average grant date fair value per share	$ 11.87	$ 11.41	$ 11.48

Stock-based Compensation Plan_5

Stock-based Compensation Plans (Schedule of Shared-Based Compensation, Performance Units (Details) - $ / shares

3 Months Ended

12 Months Ended

Nov. 30, 2021

Jan. 27, 2021

Dec. 02, 2020

Feb. 24, 2020

Jan. 28, 2020

Dec. 03, 2019

Dec. 31, 2021

Dec. 31, 2020

Dec. 31, 2019

Mar. 31, 2019

Dec. 31, 2018

Sep. 30, 2024

Sep. 30, 2023

Sep. 30, 2022

Sep. 30, 2021

Sep. 30, 2020

Sep. 30, 2019

Sep. 30, 2018

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period

62,396

Schedule of Share-based Compensation, Restricted Stock and Restricted Stock Units Activity

Restricted stock unit activity under the 2006 Plan is summarized below. Restricted stock units Weighted Weighted Aggregate Outstanding at September 30, 2019 437,022 $ 11.31 0.9 Granted 301,979 11.55 Vested (295,241) 11.40 $ 3.4 Cancelled (35,254) 11.48 Outstanding at September 30, 2020 408,506 11.41 0.9 Granted 220,795 12.29 Vested (228,121) 11.62 $ 2.8 Cancelled (5,083) 11.41 Outstanding at September 30, 2021 396,097 11.78 0.8 Granted 223,379 13.41 Vested (251,981) 11.81 $ 2.8 Cancelled (8,763) 11.87 Outstanding at September 30, 2022 358,732 $ 12.77 0.7

Performance Shares [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period

160,163

61,610

Settlement of performance-based restricted stock units, net of shares withheld for taxes

240,412,000,000

103,058,000,000

Market Based Performance Shares Member

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

230,089

4,187

234,199

7,498

2,763

147,213

Dividend yield

1.70%

1.84%

1.77%

1.73%

1.76%

1.87%

Risk-free interest rate

0.76%

0.16%

0.21%

1.23%

1.44%

1.53%

Expected life (years)

2 years 9 months 29 days

2 years 8 months 1 day

2 years 9 months 29 days

2 years 7 months 6 days

2 years 8 months 1 day

2 years 9 months 29 days

Granted, Weighted average grant date fair value per share

$ 15.76

$ 14.26

$ 15.39

$ 18.17

$ 16.76

$ 14.94

Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

57,092

2017 member [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value

$ 10.53

$ 12.50

$ 13.26

2017 member [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

100%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

54,006

2017 member [Member] | Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

59,285

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(5,279)

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

54,006

2017 member [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

135.70%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

26,294

2017 member [Member] | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

59,286

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(39,910)

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

19,376

2017 member [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

64.50%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

12,501

2017 member [Member] | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

59,290

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(39,909)

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

19,381

January 23, 2017 [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value

$ 13.15

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

100%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

19,012

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

19,012

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

0

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

19,012

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

135.70%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

25,798

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

19,011

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

0

0

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

19,011

19,011

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

64.50%

Settlement of performance-based restricted stock units, net of shares withheld for taxes

12,263

January 23, 2017 [Member] | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

19,011

November 28, 2017 [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value

$ 11.26

$ 10.53

$ 12.50

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

35,425

52,299

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

135.70%

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

0

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

57,092

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

64.50%

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

57,092

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(4,793)

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Performance Factor

90.90%

November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

57,104

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(21,679)

November 27, 2018 [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value

$ 11.86

$ 11.26

$ 10.53

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

102,203

Performance Factor

64.50%

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

110,954

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(8,751)

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

97,772

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

110,954

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(13,182)

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

82,489

Performance Factor

116.10%

90.90%

November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

110,967

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(28,478)

December 3, 2019

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value

$ 13.81

$ 11.86

$ 11.26

December 3, 2019 | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

67,597

Performance Factor

90.90%

December 3, 2019 | Share-based Payment Arrangement, Tranche One [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

69,988

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(2,391)

December 3, 2019 | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

60,375

Performance Factor

116.10%

December 3, 2019 | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

69,989

December 3, 2019 | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number

60,374

Performance Factor

70%

December 3, 2019 | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period

69,988

Forecast [Member] | November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

77,474

Forecast [Member] | November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

33,733

Forecast [Member] | November 28, 2017 [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

32,202

Forecast [Member] | November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

65,921

Forecast [Member] | November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

88,875

Forecast [Member] | November 27, 2018 [Member] | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

95,770

Forecast [Member] | December 3, 2019 | Share-based Payment Arrangement, Tranche One [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

61,446

Forecast [Member] | December 3, 2019 | Share-based Payment Arrangement, Tranche Two [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

70,096

Forecast [Member] | December 3, 2019 | Share-based Payment Arrangement, Tranche Two [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(9,614)

Forecast [Member] | December 3, 2019 | Share-based Payment Arrangement, Tranche Three [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Settlement of performance-based restricted stock units, net of shares withheld for taxes

42,262

Forecast [Member] | December 3, 2019 | Share-based Payment Arrangement, Tranche Three [Member] | PRSU base units [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period

(9,614)

Stock-based Compensation Plan_6

Stock-based Compensation Plans (Schedule of Share-based Compensation. Option Activity (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, shares	599,799	328,099	862,390
Outstanding, Weighted average exercise price (per share)	$ 12.19	$ 10.67	$ 6.11	$ 4.89
Outstanding, Weighted average remaining contractual term, years	7 years 8 months 12 days	7 years 9 months 18 days	2 years 3 months 18 days	2 years
Outstanding, Aggregate intrinsic value	$ 0.3	$ 2.7	$ 1.4	$ 5.5
Exercised, shares	(36,731)	(151,399)	(534,291)
Exercised, Weighted average exercise price (per share)	$ 5.67	$ 4.09	$ 4.15
Exercised, Aggregate intrinsic value	$ 0.2	$ 1.7	$ 3.3
Canceled, shares	(7,257)	(8,421)	0
Canceled, Weighted average exercise price (per share)	$ 0	$ 0	$ 0
Stock Options, Exercisable, Number	278,569
Exercisable, Weighted average exercise price (per share)	$ 10.12
Exercisable, Weighted average remaining contractual term, years	4 years 9 months 18 days
Exercisable, Aggregate intrinsic value	$ 0.3
Outstanding, shares	1,013,293	599,799	328,099	862,390
Granted, Weighted average exercise price (per share)	$ 13.64
Granted, shares	457,482

Stock-based Compensation Plan_7

Stock-based Compensation Plans Schedule of Share-based Compensation, Option Disclosures by Ranges of Exercise Prices (Details)	12 Months Ended
	Sep. 30, 2022 $ / shares shares
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	1,013,293
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 12.19
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	7 years 8 months 12 days
Stock Options, Exercisable, Number | shares	278,569
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 10.12
Exercise Price Range 2 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	139,969
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 8.40
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	1 year 4 months 24 days
Stock Options, Exercisable, Number | shares	139,969
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 8.40
Exercise Price Range 3
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Number of Outstanding Options | shares	873,324
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Exercise Price	$ 12.79
Stock Options, Exercise Price Range, Outstanding Options, Weighted Average Remaining Contractual Term	8 years 8 months 12 days
Stock Options, Exercisable, Number | shares	138,600
Stock Options, Exercise Price Range, Exercisable Options, Weighted Average Exercise Price	$ 11.86
Minimum [Member] | Exercise Price Range 2 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	5
Minimum [Member] | Exercise Price Range 3
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Lower Range Limit	10
Maximum [Member] | Exercise Price Range 2 [Member]
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Upper Range Limit	9.99
Maximum [Member] | Exercise Price Range 3
Share-based Payment Arrangement, Option, Exercise Price Range [Line Items]
Stock Options, Exercise Price Range, Upper Range Limit	$ 14.99

Stock-based Compensation Plan_8

Stock-based Compensation Plans (Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions) (Details) - Equity Option	Jan. 27, 2021
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.33%
Dividend yield	1.62%
Expected life (years)	6 years

Stock-based Compensation Plan_9

Stock-based Compensation Plans (Schedule of Share-based Compensation, Phantom Award Activity) (Details) - Phantom Share Units (PSUs) [Member] - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding, shares	344,844	314,475	256,154
Outstanding, Weighted average grant date fair value per share	$ 12.74	$ 11.51	$ 11.16	$ 11.61
Outstanding, Weighted average remaining contractual term	1 year 1 month 6 days	10 months 24 days	10 months 24 days	10 months 24 days
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period	203,834	185,808	188,973
Granted, Weighted average grant date fair value per share	$ 13.60	$ 11.91	$ 11.26
Vested, shares	(162,969)	(131,182)	(118,908)
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value	$ 1.6	$ 1.6	$ 1.3
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period	(46,578)	(24,257)	(11,744)
Canceled, Weighted average grant date fair value per share	$ 12.39	$ 11.30	$ 11.23
Outstanding, shares	339,131	344,844	314,475	256,154

Segment Information (Revenue an

Segment Information (Revenue and Long-Lived Assets by Geographical Areas) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 1,247.4	$ 1,111	$ 964.1
Intangible Assets, Net (Including Goodwill)	459.8	507.6
Total assets	$ 1,498.1	1,518
Document Period End Date	Sep. 30, 2022
Property, plant and equipment, net	$ 301.6	283.4
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	284.9	263.9
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	12.6	13.8
Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Property, plant and equipment, net	4.1	5.7
Mueller Co. [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	714.1	617.8	532.2
Intangible Assets, Net (Including Goodwill)	302.6	324.1
Mueller Co. [Member] | Central Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	190.9	155.1	133.6
Mueller Co. [Member] | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	653.3	563.6	485.5
Mueller Co. [Member] | Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	55	45.7	39.4
Mueller Co. [Member] | Northeast Region [Member] [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	125.3	110.4	95.1
Mueller Co. [Member] | Southeast Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	154.3	125.7	108.3
Mueller Co. [Member] | Western Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	182.8	172.4	148.5
Mueller Co. [Member] | Other International Locations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	5.8	8.5	7.3
Mueller Technologies [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	533.3	493.2	431.9
Intangible Assets, Net (Including Goodwill)	157.2	183.5
Mueller Technologies [Member] | Central Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	142.9	125.6	107.3
Mueller Technologies [Member] | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	470.3	431.4	377.5
Mueller Technologies [Member] | Northeast Region [Member] [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	115.1	100.2	112.1
Mueller Technologies [Member] | Southeast Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	109.4	106.5	76.3
Mueller Technologies [Member] | Western Region [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	102.9	99.1	81.8
Mueller Technologies [Member] | Other International Locations [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues			33.4
Customer Concentration Risk [Member] | Accounts Receivable [Member] | Ferguson Enterprises
Revenues from External Customers and Long-Lived Assets [Line Items]
Accounts and Other Receivables, Net, Current	38.6	$ 32.1
Customer Concentration Risk [Member] | Accounts Receivable [Member] | HDS IP Holdings, LLC [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Accounts and Other Receivables, Net, Current	$ 52.1		$ 48.1
Customer Concentration Risk [Member] | Sales Revenue, Goods, Gross [Member] | Ferguson Enterprises
Revenues from External Customers and Long-Lived Assets [Line Items]
10 largest customers	20%	19%	17%

Segment Information (Narrative)

Segment Information (Narrative) (Details) $ in Millions	12 Months Ended
	Sep. 30, 2022 USD ($) business_segments	Sep. 30, 2021 USD ($)	Sep. 30, 2020
Segment Reporting [Abstract]
Number of Reportable Segments | business_segments	2
Revenue, Major Customer [Line Items]
Receivables, net	$ 228	$ 212.2
Intangible Assets, Net (Including Goodwill)	459.8	507.6
Total assets	$ 1,498.1	1,518
Document Period End Date	Sep. 30, 2022
Mueller Co. [Member]
Revenue, Major Customer [Line Items]
Intangible Assets, Net (Including Goodwill)	$ 302.6	324.1
Mueller Technologies [Member]
Revenue, Major Customer [Line Items]
Intangible Assets, Net (Including Goodwill)	$ 157.2	$ 183.5
Customer Concentration Risk [Member] | Ferguson Enterprises | Sales Revenue, Goods, Gross [Member]
Revenue, Major Customer [Line Items]
10 largest customers	20%	19%	17%

Segment Information (Schedule O

Segment Information (Schedule Of Selected Supplemental Balance Sheet Information) (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Segment Reporting Information [Line Items]
Intercompany sales	$ 1,247.4	$ 1,111	$ 964.1
Operating income	111.6	131.7	116.8
Depreciation and amortization	60.5	59.6	57.8
2016	7.2	8	13
Capital expenditures	(54.7)	(62.7)	(67.7)
Property, plant and equipment, net	301.6	283.4
Total assets	$ 1,498.1	1,518
Document Period End Date	Sep. 30, 2022
Intangible Assets, Net (Including Goodwill)	$ 459.8	507.6
Mueller Co. [Member]
Segment Reporting Information [Line Items]
Intercompany sales	714.1	617.8	532.2
Operating income	118.3	120.9	104.9
Depreciation and amortization	30	30.5	28.9
2016	0.2	0.1	0
Capital expenditures	(43.4)	(51)	(57.3)
Intangible Assets, Net (Including Goodwill)	302.6	324.1
Mueller Technologies [Member]
Segment Reporting Information [Line Items]
Intercompany sales	533.3	493.2	431.9
Operating income	48.7	70.3	68.7
Depreciation and amortization	30.3	28.9	28.7
2016	0.4	(0.4)	0.7
Capital expenditures	(11.3)	(11.6)	(10.1)
Intangible Assets, Net (Including Goodwill)	157.2	183.5
Corporate [Member]
Segment Reporting Information [Line Items]
Intercompany sales	0	0	0
Operating income	(55.4)	(59.5)	(56.8)
Depreciation and amortization	0.2	0.2	0.2
2016	6.6	8.3	12.3
Capital expenditures	0	(0.1)	$ (0.3)
Intangible Assets, Net (Including Goodwill)	$ 0	$ 0

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions, $ in Millions	12 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2021 CAD ($)	Sep. 30, 2020 USD ($)
Loss Contingency, Damages Sought, Value			$ 10
Document Period End Date	Sep. 30, 2022
Product Warranty Expense	$ 9.5	$ 3.5		$ 2.6

Subsequent Events (Details)

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions				12 Months Ended
	Nov. 21, 2022	Nov. 10, 2022	Oct. 21, 2022	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Subsequent Event [Line Items]
Dividends declared, in dollars per share				$ 0.232	$ 0.22	$ 0.21
Stock Repurchased During Period, Shares				2,654,254	651,271	418,374
Stock Repurchased During Period, Value				$ 35	$ 10	$ 5
Intangible Assets, Net (Including Goodwill)				459.8	507.6
Inventories				278.7	184.7
Mueller Co. [Member]
Subsequent Event [Line Items]
Intangible Assets, Net (Including Goodwill)				302.6	324.1
Inventories				160.5	104.5
Mueller Technologies [Member]
Subsequent Event [Line Items]
Intangible Assets, Net (Including Goodwill)				157.2	183.5
Inventories				118.2	80.2
Corporate [Member]
Subsequent Event [Line Items]
Intangible Assets, Net (Including Goodwill)				0	0
Inventories				$ 0	$ 0
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date Declared			Oct. 21, 2022
Dividends declared, in dollars per share			$ 0.061
Dividends Payable, Date to be Paid	Nov. 21, 2022
Dividends Payable, Date of Record		Nov. 10, 2022

Leases, Codification Topic 84_2

Leases, Codification Topic 842 (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Lessee, Lease, Description [Line Items]
Operating Lease, Expense	$ 5.8	$ 6.1	$ 6.3
Finance Lease, Right-of-Use Asset, Amortization	1.3	1.2	1.3
Total lease expense	7.1	7.3	$ 7.6
Operating Lease, Payments	5.8	6.1
Finance Lease, Principal Payments	1.3	1.2
Operating Lease, Right-of-Use Asset	26	27.1
Finance Lease, Right-of-Use Asset, after Accumulated Amortization	1.4	2.2
Total Right of Use Assets	27.4	29.3
Operating lease liability	4.4	4
Operating Lease, Liability, Noncurrent	22.4	24.6
Finance Lease Liability, Current	0.8	1
Finance Lease, Liability, Noncurrent	0.8	1.2
Total Lease Liabilities	$ 28.4	$ 30.8
Operating Lease, Weighted Average Remaining Lease Term	6 years 8 months 1 day	7 years 9 months 25 days
Finance Lease, Weighted Average Remaining Lease Term	2 years 1 month 24 days	2 years 6 months 10 days
Operating Lease, Weighted Average Discount Rate, Percent	5.48%	5.36%
Finance Lease, Weighted Average Discount Rate, Percent	3.64%	4.24%
Lessee, Operating Lease, Liability, to be Paid, Year One	$ 5.9
Lessee, Operating Lease, Liability, to be Paid, Year Two	5.7
Lessee, Operating Lease, Liability, to be Paid, Year Three	5.1
Lessee, Operating Lease, Liability, to be Paid, Year Four	4.7
Lessee, Operating Lease, Liability, to be Paid, Year Five	3.9
Lessee, Operating Lease, Liability, to be Paid, after Year Five	7.3
Lessee, Operating Lease, Liability, to be Paid	32.6
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(5.8)
Operating Lease, Liability	26.8
Finance Lease, Liability, to be Paid, Year One	0.9
Finance Lease, Liability, to be Paid, Year Two	0.5
Finance Lease, Liability, to be Paid, Year Three	0.2
Finance Lease, Liability, to be Paid, Year Four	0.1
Finance Lease, Liability, to be Paid, Year Five	0
Finance Lease, Liability, to be Paid, after Year Five	0
Finance Lease, Liability, Payment, Due	1.7
Finance Lease, Liability, Undiscounted Excess Amount	(0.1)
Finance Lease, Liability	$ 1.6

Other Income and Expenses (Deta

Other Income and Expenses (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2019
Restructuring Costs	$ 1.5	$ 5.6
Research and Development Expense	24.5	17.1	$ 15
Advertising Expense	5.5	3.2	3.3
Interest Costs Capitalized	(2.6)	(2.3)	(0.3)
Interest Expense, Other	0.3	0.3	0.3
Interest Expense	17.6	23.8	26.6
Interest Income, Other	(0.7)	(0.4)	(1.1)
Interest expense, net	16.9	23.4	25.5
Amortization of Debt Issuance Costs	1	1.1	1.2
Severance Costs	3.2
Other, net	1.3	1.3	3.7
Restructuring Reserve	3.3	3.1	2.8	$ 1.7
Restructuring Charges	7.2	5.4	4.8
Payments for Restructuring	(7)	(5.1)	(3.7)
Inventory Write-down	1.8	5.9	4.7
Severance Costs	3.2
Other, net	1.3	1.3	3.7
Inventory Write-down	1.8	5.9	4.7
Aurora/Surrey
Inventory Write-down	2.4
Inventory Write-down	2.4
5.5% Senior Notes
Interest Expense, Debt	0	17.6	24.8
ABL Agreement
Interest Expense, Debt	0.9	0.9	0.6
4.0% Senior Notes
Interest Expense, Debt	$ 18	$ 6.2	$ 0