XML 60 R48.htm IDEA: XBRL DOCUMENT v3.10.0.1

Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions				3 Months Ended		9 Months Ended
	Aug. 20, 2018	Aug. 10, 2018	Jul. 25, 2018	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Sep. 30, 2018
Subsequent Event [Line Items]
Dividends declared, in dollars per share				$ 0.05	$ 0.04	$ 0.14	$ 0.11
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date Declared			Jul. 26, 2018
Dividends declared, in dollars per share			$ 0.0500
Dividends Payable, Date to be Paid	Aug. 20, 2018
Dividends Payable, Date of Record		Aug. 10, 2018
Domestic Line of Credit [Member]
Subsequent Event [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 225.0		$ 225.0
Domestic Line of Credit [Member] | Subsequent Event [Member]
Subsequent Event [Line Items]
Line of credit facility, Reduction of Borrowing Capacity								$ 50.0
Line of Credit Facility, Maximum Borrowing Capacity								$ 175.0

X

- Definition

Line of credit facility, Reduction of Borrowing Capacity

+ References

No definition available.

+ Details

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Namespace Prefix:	mwa_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770

+ Details

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Balance Type:	na
Period Type:	duration

X

- Definition

Date the declared dividend will be paid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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Balance Type:	na
Period Type:	duration

X

- Definition

Date the dividend to be paid was declared, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=98513485&loc=d3e4304-108586

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

X

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type:

X

- Details

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Namespace Prefix:
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Balance Type:
Period Type: