BUSINESS ACQUISITION (Narrative) (Details) $ in Thousands, bird / WK in Millions		3 Months Ended		6 Months Ended
	Jan. 06, 2017 USD ($) employee bird / WK trade_name plant	Jun. 25, 2017 USD ($) employee bird / WK	Jun. 26, 2016 USD ($)	Jun. 25, 2017 USD ($) employee bird / WK	Jun. 26, 2016 USD ($)
Business Acquisition [Line Items]
Maximum processing capacity of employees per week (in birds per week) | bird / WK		39.2		39.2
Number of employees of acquiree | employee		42,000		42,000
Administrative restructuring charges		$ 4,349	$ 0	$ 4,349	$ 0
Restructuring, GNP Acquisition
Business Acquisition [Line Items]
Administrative restructuring charges		700		100
Additional restructuring charges expected during 2017		1,800		1,800
GNP
Business Acquisition [Line Items]
Percentage of equity acquired	100.00%
Maximum processing capacity of employees per week (in birds per week) | bird / WK	2.1
Number of processing plants acquired | plant	3
Number of employees of acquiree | employee	1,750
Purchase price, amount payable	$ 2,500
Transaction costs	$ 500
Net sales of acquiree since acquisition date		115,900		213,700
Net income of acquiree since acquisition date		$ 10,200		$ 14,800
GNP | Customer relationships
Business Acquisition [Line Items]
Finite-lived intangible assets acquired, net sales growth rate used in determination of fair value	2.50%
Finite-lived intangible assets acquired, customer attrition rate used in determination of fair value	4.00%
Finite-lived intangible assets acquired, income tax rate used in determination of fair value	39.30%
Finite-lived intangible assets acquired, income tax amortization benefit factor used in determination of fair value	1.2098
Finite-lived intangible assets acquired, discount rate used in determination of fair value	13.80%
GNP | Trade names
Business Acquisition [Line Items]
Indefinite-lived trade names acquired, number of trade names valued using the income approach | trade_name	2
Indefinite-lived trade names acquired, royalty rates used in determination of fair value	2.00%
Indefinite-lived trade names acquired, net sales growth rate used in determination of fair values Acquired, Fair Value Inputs, Net Sales Growth Rate	2.50%
Indefinite-lived trade names acquired, income tax rate used in determination of fair value	39.30%
Indefinite-lived trade names acquired, income tax amortization benefit factor used in determination of fair value	1.2098
Indefinite-lived trade names acquired, royalty rate saved used in determination of fair value	13.80%