Defined Benefit Plan, Net Periodic Benefit Cost other than Service Cost

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- Definition

Intercompany Loan related to NMTC

+ References

No definition available.

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- Definition

Investment Fund Contribution for NMTC

+ References

No definition available.

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- Definition

Proceeds from Other Equity, Gross Amount from NMTC

+ References

No definition available.

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- Definition

Sub-CDE loan from NMTC

+ References

No definition available.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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- Definition

The difference between the carrying value and the sale price of real estate or properties that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
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-Subparagraph (c)
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-URI https://asc.fasb.org//1943274/2147482099/360-10-50-3

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 18
-Publisher FASB
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- Definition

Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(24))
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-Paragraph 1
-Subparagraph (SX 210.9-03(15))
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-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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Balance Type:	credit
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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
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-Topic 420
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-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SAB Topic 5.P.4(b)(1))
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-Topic 420
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-Topic 420
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-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479823/420-10-S99-1

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- Definition

Carrying amount (including both current and noncurrent portions of the accrual) as of the balance sheet date pertaining to a specified type of cost associated with exit from or disposal of business activities or restructuring pursuant to a duly authorized plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
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-Subparagraph (SAB TOPIC 5.P.4(b)(2))
-Publisher FASB
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- Definition

Amount of expense (reversal of expense) which increases (decreases) the restructuring reserve from an adjustment to a previously accrued restructuring liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 420
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (b)(2)
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-Subparagraph (SAB Topic 5.P.4(b)(2))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479823/420-10-S99-2

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Organization (Narrative) (Details) $ in Millions	3 Months Ended		6 Months Ended
Organization (Narrative) (Details) $ in Millions	Mar. 31, 2024 USD ($) business_segments	Mar. 31, 2023 USD ($)	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)
Segment Reporting Information [Line Items]
Restructuring	$ 7.2	$ 1.2	$ 7.2	$ 1.2	$ 6.6	$ 3.3
Restructuring Reserve, Accrual Adjustment			9.8	(3.0)
Gain (Loss) on Sale of Properties				4.0
Restructuring and other charges	3.2	0.7	9.8	(3.0)
Pension costs (benefits) other then service	$ 1.0	$ 1.0	$ 2.0	$ 1.9
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%	21.00%	21.00%
Number of Reportable Segments \| business_segments	2
Other Sundry Liabilities, Noncurrent	$ 3.9		$ 3.9
Proceeds from Other Equity, Gross Amount	4.8		4.8
Intercompany Loan related to NMTC	12.2		12.2
Investment Fund Contribution for NMTC	16.5		16.5
Sub-CDE loan from NMTC	16.2		16.2
Cybersecurity Related
Segment Reporting Information [Line Items]
Restructuring Reserve, Accrual Adjustment			1.5
Mueller Co. [Member]
Segment Reporting Information [Line Items]
Restructuring and other charges	$ 0.0	$ 0.0	$ 0.2	$ 0.0