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Summary of Significant Accounting Policies (Details) shares in Thousands, $ in Millions | 12 Months Ended
--- | ---
Dec. 30, 2017 USD ($) shares | Dec. 31, 2016 USD ($) reportable_segment shares | Dec. 26, 2015 USD ($) reportable_segment
Noncontrolling Interest [Line Items] |  |  |
Temporary investments | $ 0.6 | $ 40.9 |
Restricted cash | $ 6.2 | $ 9.0 |
Specified percentage over which unrecognized gains and losses are amortized | 10.00% |  |
Average remaining service period for the pension plans | 9 years |  |
Stock-based awards excluded from the computation of diluted earnings per share (in shares) | shares | 20 | 190 |
Foreign currency transaction gains (losses) | $ (0.4) | $ 0.4 | $ (1.7)
Number of reportable segments | reportable_segment |  | 3 | 2
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% |  |
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-Mueller [Member] |  |  |
Noncontrolling Interest [Line Items] |  |  |
Non-controlling ownership interest | 40.00% |  |
Mueller-Xingrong [Member] |  |  |
Noncontrolling Interest [Line Items] |  |  |
Non-controlling ownership interest | 49.50% |  |

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