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Commitments and Contingencies, Environmental (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2016 USD ($) Party Property | Dec. 26, 2015 USD ($) | Dec. 27, 2014 USD ($)
Site Contingency [Line Items] |  |  |
Environmental expense | $ 0.9 | $ 0.1 | $ 1.2
Environmental reserves | 21.9 | $ 21.7 |
Expected environmental expenditures for 2017 | 0.7 |  |
Expected environmental expenditures for 2018 | 0.6 |  |
Expected environmental expenditures for 2019 | 0.6 |  |
Expected environmental expenditures for 2020 | 0.7 |  |
Expected environmental expenditures for 2021 | 0.7 |  |
Expected environmental expenditures after 2021 | $ 18.6 |  |
Operating Properties [Member] | Mueller Copper Tube Products, Inc. [Member] |  |  |
Site Contingency [Line Items] |  |  |
Estimated number of years until mitigation resolution | 9 years |  |
Operating Properties [Member] | Mueller Copper Tube Products, Inc. [Member] | Minimum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | $ 0.9 |  |
Operating Properties [Member] | Mueller Copper Tube Products, Inc. [Member] | Maximum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | 1.4 |  |
Non-Operating Properties [Member] | Southeast Kansas Sites [Member] |  |  |
Site Contingency [Line Items] |  |  |
Environmental reserves | $ 5.6 |  |
Number of parties involved in settlement negotiations | Party | 2 |  |
Non-Operating Properties [Member] | Shasta Area Mine Sites [Member] |  |  |
Site Contingency [Line Items] |  |  |
Environmental spending | $ 1.2 |  |
Period of permit, implementation of Best Management Practices | 10 years |  |
Estimated number of years until mitigation resolution | 30 years |  |
Non-Operating Properties [Member] | Shasta Area Mine Sites [Member] | Minimum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | $ 13.2 |  |
Non-Operating Properties [Member] | Shasta Area Mine Sites [Member] | Maximum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | 20.9 |  |
Non-Operating Properties [Member] | Lead Refinery Site [Member] |  |  |
Site Contingency [Line Items] |  |  |
Environmental expense | $ 0.5 |  |
Number of parties involved in settlement negotiations | Party | 3 |  |
Estimated number of years until mitigation resolution | 20 years |  |
Lead Refinery Site [Abstract] |  |  |
EPA's estimated cost of site remediation | $ 26.0 |  |
Number of surrounding properties | Property | 300 |  |
Non-Operating Properties [Member] | Lead Refinery Site [Member] | Minimum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | $ 2.1 |  |
Non-Operating Properties [Member] | Lead Refinery Site [Member] | Maximum [Member] |  |  |
Site Contingency [Line Items] |  |  |
Mitigation estimates | $ 4.7 |  |

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