XML 49 R32.htm IDEA: XBRL DOCUMENT v3.21.2

Summary of Significant Accounting Policies (Tables)

12 Months Ended

Sep. 30, 2021

Sep. 30, 2020

Accounting Policies [Abstract]

Financing Receivable, Current, Allowance for Credit Loss [Table Text Block]

The following table summarizes information concerning our allowance for credit losses.

			2021						2020						2019
			(in millions)
Balance at beginning of year			$	2.5					$	1.5					$	1.4
Provision charged to expense			1.1						1.1						0.3
Other			(0.1)						(0.1)						(0.2)
Balance at end of year			$	3.5					$	2.5					$	1.5

Schedule of Reserves for Excess and Obsolete Inventory

The following table summarizes information concerning our inventory valuation reserves.

			2021						2020						2019
			(in millions)
Balance at beginning of year			$	11.7					$	7.5					$	5.1
Provision charged to expense			5.9						4.7						3.4
Inventory disposed			(3.6)						(0.7)						(1.2)
Other			0.8						0.2						0.2
Balance at end of year			$	14.8					$	11.7					$	7.5

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.

			2021						2020						2019
			(in millions)
Balance at beginning of year			$	14.4					$	17.1					$	20.0
Warranty accruals			3.5						2.6						3.9
Warranty costs			(8.2)						(5.3)						(6.8)
Balance at end of year			$	9.7					$	14.4					$	17.1

X

- Definition

Schedule of Reserves for Excess and Obsolete Inventory [Table Text Block]

+ References

No definition available.

+ Details

Name:	mwa_ScheduleOfReservesForExcessAndObsoleteInventoryTableTextBlock
Namespace Prefix:	mwa_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- References

No definition available.

+ Details

Name:	us-gaap_AccountingPoliciesAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of allowance for credit loss of financing receivable, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953423-111524

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919249-210447

+ Details

Name:	us-gaap_ScheduleOfCreditLossesForFinancingReceivablesCurrentTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Tabular disclosure of the changes in the guarantor's aggregate product warranty liability, including the beginning balance of the aggregate product warranty liability, the aggregate reductions in that liability for payments made (in cash or in kind) under the warranty, the aggregate changes in the liability for accruals related to product warranties issued during the reporting period, the aggregate changes in the liability for accruals related to preexisting warranties (including adjustments related to changes in estimates), and the ending balance of the aggregate product warranty liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=123368208&loc=d3e12565-110249

+ Details

Name:	us-gaap_ScheduleOfProductWarrantyLiabilityTableTextBlock
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:textBlockItemType
Balance Type:	na
Period Type:	duration