Represents the average remaining service period for the pension plans.

No definition available.

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- Definition

Represents the number of shares given as stock dividend for each outstanding share in a stock split.

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Represents the unrecognized gains and losses which are amortized when the net gains and losses exceed specified percent of the greater of the market value of the plan assets or the projected benefit obligation.

+ References

No definition available.

+ Details

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- Definition

Temporary investments with original maturities of less than three months.

+ References

No definition available.

+ Details

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Antidilution

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Diluted Earnings Per Share

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Contingent Stock Agreement

-URI http://asc.fasb.org/extlink&oid=6508534

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- Definition

Amount before tax of foreign currency transaction realized and unrealized gain (loss) recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 20

-Section 45

-Paragraph 1

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-Topic 830

-SubTopic 20

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6450189&loc=d3e30700-110894

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Balance Type:	credit
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- Definition

The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

+ References

No definition available.

+ Details

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- Definition

Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

+ Details

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- Definition

The carrying amounts of cash and cash equivalent items which are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. This element is for unclassified presentations; for classified presentations there is a separate and distinct element.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 1

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

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-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.1)

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- Definition

Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6525746

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-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 4

-Subparagraph (SAB TOPIC 4.C)

-URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770

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Summary of Significant Accounting Policies (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
	Dec. 27, 2014	Dec. 28, 2013	Dec. 29, 2012
Principles of consolidation [Abstract]
Non-controlling ownership interest of Mueller-Xingrong (in hundredths)	49.50%
Common Stock Split [Abstract]
Conversion ratio for stock split	2
Number of shares given as stock dividend for each outstanding share (in shares)	1
Cash equivalents [Abstract]
Temporary investments	$ 144.9mli_TemporaryInvestments	$ 179.2mli_TemporaryInvestments
Restricted cash	8.1	5.2
Benefit Plans [Abstract]
Specified percentage over which unrecognized gains and losses are amortized (in hundredths)	10.00%
Average remaining service period for the pension plans	9 years
Earnings Per Share [Abstract]
Stock-based awards excluded from the computation of diluted earnings per share (in shares)	180,000
Foreign currency translation [Abstract]
Foreign currency transaction (losses) gains	$ 0.1	$ (0.1)	$ (0.3)
Buildings [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life	20 years
Buildings [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life	40 years
Machinery and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Abstract]
Property, plant and equipment, useful life	20 years