FAIR VALUE (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Assets:
Marketable Securities	$ 99,282	$ 179,125
Fair Value, Measurements, Recurring [Member]
Assets:
Marketable Securities	99,282	179,125
Total assets	104,826	181,901
Liabilities:
Contingent consideration	2,100	7,086
Deferred compensation	27,385	25,397
Total liabilities	41,160	41,919
Fair Value, Measurements, Recurring [Member] | Foreign exchange contracts
Assets:
Assets	5,544	2,776
Liabilities:
Liabilities	804	4,351
Fair Value, Measurements, Recurring [Member] | Interest Rate Swap [Member]
Liabilities:
Liabilities	10,871	5,085
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1)
Assets:
Marketable Securities	0	0
Total assets	0	0
Liabilities:
Contingent consideration	0	0
Deferred compensation	0	0
Total liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Foreign exchange contracts
Assets:
Assets	0	0
Liabilities:
Liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets or Liabilities (Level 1) | Interest Rate Swap [Member]
Liabilities:
Liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2)
Assets:
Marketable Securities	99,282	179,125
Total assets	104,826	181,901
Liabilities:
Contingent consideration	0	0
Deferred compensation	27,385	25,397
Total liabilities	39,060	34,833
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Foreign exchange contracts
Assets:
Assets	5,544	2,776
Liabilities:
Liabilities	804	4,351
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) | Interest Rate Swap [Member]
Liabilities:
Liabilities	10,871	5,085
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3)
Assets:
Marketable Securities	0	0
Total assets	0	0
Liabilities:
Contingent consideration	2,100	7,086
Deferred compensation	0	0
Total liabilities	2,100	7,086
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) | Foreign exchange contracts
Assets:
Assets	0	0
Liabilities:
Liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) | Interest Rate Swap [Member]
Liabilities:
Liabilities	$ 0	$ 0