REVENUE DISAGGREGATION OF REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Net sales	$ 550,047	$ 638,996	$ 1,151,278	$ 1,217,310
Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	294,275	280,673	584,452	511,305
Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	255,772	358,323	566,826	706,005
Defense Aerospace [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	109,305	104,426	211,133	183,213
Defense Ground [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	20,029	26,394	42,686	47,151
Naval [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	164,941	149,853	330,633	280,941
Commercial Aerospace [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	71,084	108,000	171,765	211,222
Power Generation [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	76,202	93,171	160,550	189,652
General Industrial [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 108,486	$ 157,152	$ 234,511	$ 305,131
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Net Sales, Net, Percent	54.00%	48.00%	53.00%	48.00%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Net Sales, Net, Percent	46.00%	52.00%	47.00%	52.00%