INTANGIBLE ASSETS (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 523,998	$ 447,995	$ 441,361
Identifiable intangible assets [Abstract]
Gross carrying amount	323,848	263,790
Accumulated amortization	179,924	154,385
Finite-Lived Intangible Assets, Amortization Expense, Maturity Schedule [Abstract]
Amortization of identifiable intangible assets	25,789	24,988	$ 26,784
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2020	27,020
2021	23,246
2022	21,327
2023	18,710
2024	9,759
Customer relationships and lists
Identifiable intangible assets [Abstract]
Gross carrying amount	239,578	192,185
Accumulated amortization	$ 139,863	122,545
Customer relationships and lists | Minimum
Identifiable intangible assets [Abstract]
Amortization period	10 years
Customer relationships and lists | Maximum
Identifiable intangible assets [Abstract]
Amortization period	20 years
Trademarks & trade names
Identifiable intangible assets [Abstract]
Gross carrying amount	$ 43,102	39,934
Accumulated amortization	$ 20,477	16,755
Trademarks & trade names | Minimum
Identifiable intangible assets [Abstract]
Amortization period	2 years
Trademarks & trade names | Maximum
Identifiable intangible assets [Abstract]
Amortization period	17 years
Developed technology
Identifiable intangible assets [Abstract]
Gross carrying amount	$ 20,206	13,338
Accumulated amortization	$ 11,008	8,604
Developed technology | Minimum
Identifiable intangible assets [Abstract]
Amortization period	5 years
Developed technology | Maximum
Identifiable intangible assets [Abstract]
Amortization period	12 years
Other
Identifiable intangible assets [Abstract]
Gross carrying amount	$ 20,962	18,333
Accumulated amortization	$ 8,576	$ 6,481
Other | Minimum
Identifiable intangible assets [Abstract]
Amortization period	3 years
Other | Maximum
Identifiable intangible assets [Abstract]
Amortization period	18 years