PENSION AND OTHER POSTRETIREMENT BENEFITS (Schedule of Defined Benefit Plan Obligations and Assets) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 24, 2017	Sep. 25, 2016	Sep. 24, 2017	Sep. 25, 2016	Dec. 25, 2016	Dec. 27, 2015
Change in plan assets:
Fair value of plan assets, beginning of period			$ 97,526
Fair value of plan assets, end of period	$ 109,814		109,814
Pension Benefits
Change in projected benefit obligation:
Projected benefit obligation, beginning of period			167,159	$ 165,952
Interest cost	1,392	$ 1,396	4,178	4,189
Actuarial losses (gains)			9,433	12,233
Benefits paid			(7,571)	(7,274)
Projected benefit obligation, end of period	173,199	175,100	173,199	175,100
Change in plan assets:
Fair value of plan assets, beginning of period			97,526	96,947
Actual return on plan assets			9,321	4,769
Contributions by employer			10,538	8,983
Benefits paid			(7,571)	(7,274)
Fair value of plan assets, end of period	109,814	103,425	109,814	103,425
Funded status:
Unfunded benefit obligation, end of period	(63,385)		(63,385)		$ (69,633)
Amounts recognized in the Condensed Consolidated and Combined Balance Sheets at end of period:
Current liability	(13,098)		(13,098)		(13,113)
Long-term liability	(50,287)		(50,287)		(56,520)
Recognized liability	(63,385)		(63,385)		(69,633)
Amounts recognized in accumulated other comprehensive loss at end of period:
Net actuarial loss (gain)	49,847	49,026	49,847	49,026	46,494	$ 38,115
Other Benefits
Change in projected benefit obligation:
Projected benefit obligation, beginning of period			1,648	1,672
Interest cost	13	12	38	38
Actuarial losses (gains)			25	95
Benefits paid			(111)	(105)
Projected benefit obligation, end of period	1,600	1,700	1,600	1,700
Change in plan assets:
Fair value of plan assets, beginning of period			0	0
Actual return on plan assets			0	0
Contributions by employer			111	105
Benefits paid			(111)	(105)
Fair value of plan assets, end of period	0	0	0	0
Funded status:
Unfunded benefit obligation, end of period	(1,600)		(1,600)		(1,648)
Amounts recognized in the Condensed Consolidated and Combined Balance Sheets at end of period:
Current liability	(147)		(147)		(147)
Long-term liability	(1,453)		(1,453)		(1,501)
Recognized liability	(1,600)		(1,600)		(1,648)
Amounts recognized in accumulated other comprehensive loss at end of period:
Net actuarial loss (gain)	$ (6)	$ 16	$ (6)	$ 16	$ (31)	$ (79)