DERIVATIVES (INCOME STATEMENT CLASSIFICATION) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivative Instruments, Gain (Loss) [Line Items]
Revenues	$ 419,133	$ 364,936	$ 349,853	$ 375,249	$ 426,623	$ 359,036	$ 353,429	$ 338,277	$ 1,509,171	$ 1,477,365	$ 1,275,258
Interest Expense.									28,674	13,734	7,943
Other nonoperating income expense									(11,618)	1,869	$ 6,855
Designated as Hedging Instruments [Member] | Foreign Exchange [Member] | Cash Flow [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in other comprehensive income (loss) - effective portion, net of tax:									(12,810)	(14,336)
Designated as Hedging Instruments [Member] | Foreign Exchange [Member] | Cash Flow [Member] | Reclassification from accumulated other comprehensive income | Revenue
Derivative Instruments, Gain (Loss) [Line Items]
Revenues									(17,548)	(22,792)
Designated as Hedging Instruments [Member] | Interest Rate | Cash Flow [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Amount of gain or (loss) recognized in other comprehensive income (loss) - effective portion, net of tax:										(70)
Designated as Hedging Instruments [Member] | Interest Rate | Cash Flow [Member] | Reclassification from accumulated other comprehensive income | Interest Expense
Derivative Instruments, Gain (Loss) [Line Items]
Interest Expense.										(115)
Not Designated as Hedging Instruments [Member] | Foreign Exchange [Member] | Fair Value [Member] | Reclassification from accumulated other comprehensive income | Other income (expense), net
Derivative Instruments, Gain (Loss) [Line Items]
Other nonoperating income expense									$ (7,436)	$ 1,350