ACQUISITIONS (Fair Values and Useful Lives of Intangible Assets Acquired) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($)
Continuum
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair value of intangible assets acquired	$ 14,450
Continuum | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	6 years 6 months 12 days
Estimated fair value of intangible assets acquired	$ 5,800
Continuum | Favorable lease
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	11 years 2 months
Estimated fair value of intangible assets acquired	$ 5,500
Continuum | Contract royalties
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	8 years
Estimated fair value of intangible assets acquired	$ 1,900
Continuum | Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	5 years
Estimated fair value of intangible assets acquired	$ 1,250
Think
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair value of intangible assets acquired	$ 6,882
Think | Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	7 years
Estimated fair value of intangible assets acquired	$ 6,117
Think | Favorable lease
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair value of intangible assets acquired	0
Think | Contract royalties
Acquired Finite-Lived Intangible Assets [Line Items]
Estimated fair value of intangible assets acquired	$ 0
Think | Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Weighted average useful life	5 years
Estimated fair value of intangible assets acquired	$ 765