RESTRUCTURING (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Mar. 28, 2020
Restructuring Cost and Reserve [Line Items]
Restructuring and turnaround costs	$ 4,440	$ 3,757	$ 8,440	$ 5,784
Restructuring liability	1,680		1,680		$ 2,648
Restructuring liability payable in next twelve months	1,200		1,200
Turnaround costs	4,513	2,414	7,448	3,472
2020 Program
Restructuring Cost and Reserve [Line Items]
Restructuring and turnaround costs	4,400	2,900	8,000	2,900
Cumulative costs to date	19,800		19,800
Restructuring liability	1,091		1,091		$ 1,136
2020 Program | Minimum
Restructuring Cost and Reserve [Line Items]
Expected cost	60,000		60,000
2020 Program | Maximum
Restructuring Cost and Reserve [Line Items]
Expected cost	70,000		70,000
2018 Program
Restructuring Cost and Reserve [Line Items]
Restructuring and turnaround costs		$ 900	500	$ 2,900
Cumulative costs to date	$ 58,700		$ 58,700