RESTRUCTURING (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016	Nov. 01, 2017	Apr. 01, 2017
Restructuring Cost and Reserve [Line Items]
Restructuring and turnaround costs	$ 5,787	$ 1,597	$ 8,270	$ 20,413
Restructuring liability	4,333		4,333			$ 7,468
Restructuring liability payable in next twelve months	3,900		3,900
Restructuring costs	151	(354)	1,207	16,032
Turnaround costs	5,636	1,951	7,063	4,381
Severance and Other Employee Costs
Restructuring Cost and Reserve [Line Items]
Restructuring liability	3,575		3,575			$ 7,001
Restructuring costs			446
2017 Program [Member]
Restructuring Cost and Reserve [Line Items]
Restructuring and turnaround costs	$ 5,200	$ 1,100	$ 7,700	$ 18,800
Subsequent Event [Member] | 2018 Program [Member] | Minimum
Restructuring Cost and Reserve [Line Items]
Expected cost					$ 50,000
Subsequent Event [Member] | 2018 Program [Member] | Minimum | Severance and Other Employee Costs
Restructuring Cost and Reserve [Line Items]
Expected cost					35,000
Subsequent Event [Member] | 2018 Program [Member] | Maximum
Restructuring Cost and Reserve [Line Items]
Expected cost					60,000
Subsequent Event [Member] | 2018 Program [Member] | Maximum | Severance and Other Employee Costs
Restructuring Cost and Reserve [Line Items]
Expected cost					$ 40,000