XML 54 R43.htm IDEA: XBRL DOCUMENT v3.6.0.2

Subsequent Events (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions				3 Months Ended			12 Months Ended
	Feb. 21, 2017	Feb. 10, 2017	Jan. 05, 2017	Mar. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2016	Feb. 07, 2017
Subsequent Event [Line Items]
Dividends declared, in dollars per share					$ 0.03	$ 0.02
Business Acquisition, Revenue Reported by Acquired Entity for Last Annual Period							$ 15
Subsequent Event [Member]
Subsequent Event [Line Items]
Dividends Payable, Date Declared			Jan. 05, 2017
Dividends declared, in dollars per share			$ 0.0400
Dividends Payable, Date to be Paid	Feb. 21, 2017
Dividends Payable, Date of Record		Feb. 10, 2017
Disposal Date				Jan. 06, 2017
Business Acquisition, Date of Acquisition Agreement				Jan. 30, 2017
Payments to Acquire Businesses, Gross				$ 26
Subsequent Event, Date				Feb. 06, 2017
Accelerated Share Repurchases, Settlement (Payment) or Receipt								$ 50
Accelerated Share Repurchases, Initial Shares								2.9

X

- Definition

The initial number of shares transferred to the Company under an Accelerated Share Repurchase agreement, subject to final adjustment.

+ References

No definition available.

+ Details

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Namespace Prefix:	mwa_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Amount of cash receipt from (payment to) bank; or stock received from (issuance to) bank in the settlement of the accelerated share repurchase agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 30
-Section 25
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6405686&loc=d3e22802-112653

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Date when the business acquisition agreement was executed, 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

Total revenue reported by the acquired entity for its previous full fiscal year before the business acquisition.

+ References

No definition available.

+ Details

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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
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X

- Definition

Date the entity disposed of a business or a group of assets, in CCYY-MM-DD format.

+ References

No definition available.

+ Details

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Balance Type:	na
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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=6367179&loc=d3e4304-108586

+ Details

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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=6367179&loc=d3e4304-108586

+ Details

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Namespace Prefix:	us-gaap_
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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_
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X

- Definition

The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Investing Activities
-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3213-108585

+ Details

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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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X

- Definition

Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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- Details

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