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Benefit Plans - Contributions and Benefit Payments, Multiemployer Plan, 401(k) Plans and UMWA Benefit Plans (Details) $ in Thousands | 12 Months Ended
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Dec. 29, 2018 USD ($) bargain_agreement | Dec. 30, 2017 USD ($) | Dec. 31, 2016 USD ($)
IAM Plan Trusts [Abstract] |  |  |
Number of collective bargaining agreements | bargain_agreement | 2 |  |
Pension contributions under the I.A.M. pension plan trusts | $ 1,300 | $ 1,100 | $ 1,100
Maximum percentage of employer contributions (less than) | 5.00% |  |
401 (k) Plan [Abstract] |  |  |
Compensation expense for the Company's matching contribution | $ 5,100 | 5,100 | 5,200
Contributions to UMWA 1992 Benefit Plan | $ 153 | $ 182 | $ 197

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- Definition Amount of contributions to the United Mine Workers of America 1992 Benefit Plan. + References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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- Definition The maximum percentage of employer contributions related to a defined pension plan or trust during the period. + References No definition available. + Details
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- Definition The number of collective bargaining agreements related to negotiation on participation on defined benefit plan. + References No definition available. + Details
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- Definition Amount of cost for defined contribution plan. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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- Definition Amount of contributions made to multiemployer plan by employer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450691-114947 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450702-114947 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 80 -Section 50 -Paragraph 5 -Subparagraph (e)(1) -URI http://asc.fasb.org/extlink&oid=65877416&loc=SL14450657-114947 + Details
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