CUSTOMER CONTRACTS, TRADENAMES AND TRADEMARKS, AND OTHER INTANGIBLE ASSETS - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Intangible assets
Amortization Expenses	$ 53,600	$ 47,700	$ 44,500
Trademarks & Tradenames, Net
Intangible assets
Gross intangible assets	102,700	97,400
Internet domains
Intangible assets
Gross intangible assets	2,200	2,200
Customer Contracts, Net
Intangible assets
Finite-Lived Intangible Assets, Net	325,929	298,949
Customer Contracts, Net | International
Intangible assets
Finite-Lived Intangible Assets, Net	$ 42,100	45,700
Customer Contracts, Net | Minimum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	7 years
Customer Contracts, Net | Maximum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	20 years
Trademarks & Tradenames, Net
Intangible assets
Gross intangible assets	$ 115,468	115,131
Trademarks & Tradenames, Net | International
Intangible assets
Finite-Lived Intangible Assets, Net	$ 2,900	3,300
Trademarks & Tradenames, Net | Minimum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	7 years
Trademarks & Tradenames, Net | Maximum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	20 years
Other Intangible Assets, Net
Intangible assets
Gross intangible assets	$ 24,448	23,247
Other Intangible Assets, Net | International
Intangible assets
Finite-Lived Intangible Assets, Net	$ 700	$ 1,000
Non-compete agreements | Minimum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	3 years
Non-compete agreements | Maximum
Intangible assets
Finite-Lived Intangible Asset, Useful Life	20 years
Patents
Intangible assets
Finite-Lived Intangible Asset, Useful Life	15 years