REVENUE RECOGNITION Contract Assets, Liabilities and Receivables (Details) - USD ($) $ in Thousands	3 Months Ended
Jun. 30, 2018	Mar. 31, 2018
Disaggregation of Revenue [Line Items]
Accounts receivable	$ 259,800	$ 246,980
Contract with Customer, Liability	13,300	13,300
Contract with Customer, Liability, Revenue Recognized	9,100
Contract with Customer, Asset, Net	0	0
Contract with Customer, Performance Obligation Satisfied in Previous Period	1,000
Revenue from Contract with Customer [Member]
Disaggregation of Revenue [Line Items]
Accounts receivable	$ 195,600	$ 176,500

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

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