Represents the average remaining service period for the pension plans.

No definition available.

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- 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.

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- Definition

Temporary investments with original maturities of less than three months.

+ References

No definition available.

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- Definition

Amount of allowance for credit loss on accounts receivable, classified as current.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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/disclosureRef
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

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

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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Balance Type:	credit
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- Definition

Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

Term of lessee's operating lease renewal, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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- 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.

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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 26, 2020	Dec. 28, 2019	Dec. 29, 2018
Noncontrolling Interest [Line Items]
Temporary investments	$ 13,300	$ 500
Allowance for doubtful accounts	$ 1,538	$ 770
Operating lease renewal term	5 years
Specified percentage over which unrecognized gains and losses are amortized	10.00%
Average remaining service period for the pension plans	11 years 6 months
Stock-based awards excluded from the computation of diluted earnings per share (in shares)	10,000	0
Foreign currency transaction gains (losses)	$ (500)	$ 200	$ (1,000)
Minimum [Member]
Noncontrolling Interest [Line Items]
Operating lease, lease term	1 year
Maximum [Member]
Noncontrolling Interest [Line Items]
Operating lease, lease term	15 years
Tecumseh Products Holdings LLC [Member]
Noncontrolling Interest [Line Items]
Equity method investment, ownership percentage	50.00%
Second Unconsolidated Affiliate [Member]
Noncontrolling Interest [Line Items]
Equity method investment, ownership percentage	50.00%
Mueller Middle East BSC [Member]
Noncontrolling Interest [Line Items]
Equity method investment, ownership percentage	40.00%
Building [Member] \| Minimum [Member]
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life	20 years
Building [Member] \| Maximum [Member]
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life	40 years
Machinery and Equipment [Member] \| Minimum [Member]
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life	5 years
Machinery and Equipment [Member] \| Maximum [Member]
Noncontrolling Interest [Line Items]
Property, plant and equipment, useful life	20 years
Jungwoo Metal Ind. Co., LTD [Member]
Noncontrolling Interest [Line Items]
Non-controlling ownership interest	40.00%