REVENUE DISAGGREGATION OF REVENUE (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Disaggregation of Revenue [Line Items]
Net sales	$ 620,298	$ 567,653	$ 1,167,820	$ 1,091,244
Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	253,967	212,894	459,281	395,936
Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	366,331	354,759	708,539	695,308
Defense Aerospace [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	98,268	89,367	174,209	154,661
Defense Ground [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	20,272	17,515	42,282	37,251
Naval [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	132,005	100,048	234,786	191,018
Defense Other [Member] | Defense [Member]
Disaggregation of Revenue [Line Items]
Net sales	3,422	5,964	8,004	13,006
Commercial Aerospace [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	104,617	100,353	204,021	198,966
Power Generation [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	102,075	114,773	201,087	220,324
General Industrial [Member] | Commercial [Member]
Disaggregation of Revenue [Line Items]
Net sales	$ 159,639	$ 139,633	$ 303,431	$ 276,018
Transferred over Time [Member]
Disaggregation of Revenue [Line Items]
Net Sales, Net, Percent	31.00%		31.00%
Transferred at Point in Time [Member]
Disaggregation of Revenue [Line Items]
Net Sales, Net, Percent	69.00%		69.00%