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Retirement Plans - Additional Information (Detail) - USD ($) | 12 Months Ended
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Dec. 29, 2017 | Dec. 30, 2016 | Jan. 01, 2016
Retirement Plan Disclosure [Line Items] |  |  |
Defined Contribution Plan Employer Contribution Percentage Of Eligible Wages | 7.00% |  |
Defined Contribution Plan Employer Contribution Annual Vesting Percentage | 20.00% |  |
Defined Contribution Plan Employer Contribution Annual Vesting Period | 5 years |  |
Pension and Other Postretirement Benefit Expense | $ 7,914,000 | $ 7,761,000 | $ 7,317,000

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- Definition Amount of cost (reversal of cost) for pension and other postretirement benefits. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(b)(4)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03(b)(2)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 Reference 4: http://www.xbrl.org/2003/role/presentationRef -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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