STOCKHOLDERS' EQUITY (Schedule of Reclassification from Accumulated Other Comprehensive Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 25, 2017	Jun. 26, 2016	Jun. 25, 2017	Jun. 26, 2016
Amortization of defined benefit pension and other postretirement plan actuarial losses:
Realized gain on sale of securities	$ 1,044	$ 683	$ 1,346	$ 1,376
Amortization of defined benefit pension and other postretirement plan actuarial losses	(1,826,217)	(1,742,184)	(3,631,504)	(3,467,559)
Amortization of defined benefit pension and other postretirement plan actuarial losses	$ (61,636)	$ (49,520)	(124,489)	(98,308)
Total before tax			(466)	204
Tax benefit (expense)			176	(77)
Net income			(290)	127
Amount Reclassified from Accumulated Other Comprehensive Loss
Amortization of defined benefit pension and other postretirement plan actuarial losses:
Realized gain on sale of securities			0	534
Amount Reclassified from Accumulated Other Comprehensive Loss | Union Plan
Amortization of defined benefit pension and other postretirement plan actuarial losses:
Amortization of defined benefit pension and other postretirement plan actuarial losses			(12)	(10)
Amount Reclassified from Accumulated Other Comprehensive Loss | Legacy Gold Kist Plans
Amortization of defined benefit pension and other postretirement plan actuarial losses:
Amortization of defined benefit pension and other postretirement plan actuarial losses			(142)	(100)
Amortization of defined benefit pension and other postretirement plan actuarial losses			$ (312)	$ (220)