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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% |  |

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