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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. 31, 2016 USD ($) Agreement | Dec. 26, 2015 USD ($) | Dec. 27, 2014 USD ($)
IAM Plan Trusts [Abstract] |  |  |
Number of collective bargaining agreements | Agreement | 2 |  |
Pension contributions under the I.A.M. pension plan trusts | $ 1,100 | $ 1,100 | $ 1,000
Maximum percentage of employer contributions | 5.00% |  |
Maximum percentage funded in the red zone, under the Pension Protection act of 2006 | 65.00% |  |
Maximum percentage funded in the yellow zone, under the Pension Protection act of 2006 | 80.00% |  |
Minimum percentage funded in the green zone, under the Pension Protection act of 2006 | 80.00% |  |
401 (k) Plan [Abstract] |  |  |
Compensation expense for the Company's matching contribution | $ 5,200 | 4,200 | 4,100
Contributions to UMWA 1992 Benefit Plan | 197 | $ 214 | $ 249
Pension Benefits [Member] |  |  |
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract] |  |  |
2017 | 10,496 |  |
2018 | 10,491 |  |
2019 | 10,496 |  |
2020 | 10,431 |  |
2021 | 10,388 |  |
2022-2026 | 51,211 |  |
Total | 103,513 |  |
Company's expected contribution to benefit plans in next fiscal year | 900 |  |
Other Benefits [Member] |  |  |
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract] |  |  |
2017 | 1,179 |  |
2018 | 1,100 |  |
2019 | 1,052 |  |
2020 | 1,294 |  |
2021 | 1,102 |  |
2022-2026 | 5,902 |  |
Total | 11,629 |  |
Company's expected contribution to benefit plans in next fiscal year | $ 1,200 |  |

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- Definition The total amount of benefits expected to be paid ten years after the date of the latest statement of financial position. + References No definition available. + Details
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- Definition The maximum percentage funded in the red zone, under the Pension Protection Act of 2006 for the I.A.M. Plan trust. + References No definition available. + Details
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- Definition The minimum percentage funded in the green zone, under the Pension Protection Act of 2006 for the I.A.M. Plan trust. + References No definition available. + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (g) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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