EMPLOYEE BENEFITS (Details) $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 29, 2016 USD ($)	Mar. 27, 2016 USD ($) item	Mar. 29, 2015 USD ($)
EMPLOYEE BENEFITS
Number of new participants | item		0
Retirement expense for continuing operations
Net pension expense		$ 3,694	$ 2,493
Pension plan
Retirement expense for continuing operations
Service cost		4,700	2,920
Interest cost		22,167	21,248
Expected return on plan assets		(27,107)	(26,571)
Actuarial loss		4,596	5,549
Net pension expense		4,356	3,146
Value of contributions to plan	$ 47,100
Post-retirement plans
Retirement expense for continuing operations
Net pension expense		$ (662)	$ (653)