Income Taxes Components of Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	Dec. 27, 2014	Dec. 28, 2013
Income Tax Disclosure [Abstract]
Inventories	$ 2,842us-gaap_DeferredTaxAssetsInventory	$ 2,226us-gaap_DeferredTaxAssetsInventory
Retirement benefits	3,215	3,408
State net operating losses	3,417	2,936
Federal net operating losses	3,503	0
State tax credit carryforwards	1,740	1,740
Federal tax credit carryforwards	2,472	0
Allowances for bad debts, claims and discounts	3,175	2,527
Other	4,776us-gaap_DeferredTaxAssetsOther	5,279us-gaap_DeferredTaxAssetsOther
Total deferred tax assets	25,140us-gaap_DeferredTaxAssetsGross	18,116us-gaap_DeferredTaxAssetsGross
Valuation allowance	(4,317)	(3,748)
Net deferred tax assets	20,823us-gaap_DeferredTaxAssetsNet	14,368us-gaap_DeferredTaxAssetsNet
Property, plant and equipment	17,477	11,818
Total deferred tax liabilities	17,477us-gaap_DeferredIncomeTaxLiabilities	11,818us-gaap_DeferredIncomeTaxLiabilities
Net deferred tax asset	3,346us-gaap_DeferredTaxAssetsLiabilitiesNet	2,550us-gaap_DeferredTaxAssetsLiabilitiesNet
Current deferred tax assets	12,722	6,622
Non-current deferred tax liabilities	$ (9,376)	$ (4,072)

Amount of deferred tax liability attributable to taxable temporary differences.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Deferred Tax Liability

-URI http://asc.fasb.org/extlink&oid=6510232

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6907707&loc=d3e32537-109319

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 15

-Subparagraph b(2)

-Article 7