SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Accounting Policies [Abstract]
Depreciation	$ 11,600	$ 10,800	$ 14,400
Deferred tax assets	21,427	35,794
Non-cash compensation	25,040	17,887	16,295
Share-based compensation, tax benefit recognized	4,600	4,300	6,400
Advertising expense	$ 8,500	$ 7,000	$ 6,500
Maximum [Member] | Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible assets	3 years
Maximum [Member] | Acquired Names [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible assets	5 years
Minimum [Member] | Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Estimated useful life of intangible assets	2 years