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LONG-TERM DEBT - Schedule Of Cash Flow Hedges Related to Derivative Instruments On the Balance Sheet (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, assets	$ 6		$ 6		$ 820
Cash flow hedge derivatives, liabilities	5,460		5,460		1,942
Unrealized (loss) gain resulting from changes in fair value of derivative instruments	(2,965)	$ (145)	(4,519)	$ 640
Other current assets \| Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, assets	6		6		338
Other non-current assets \| Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, assets	0		0		482
Other accrued liabilities \| Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, liabilities	1,308		1,308		387
Other long-term liabilities \| Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Cash flow hedge derivatives, liabilities	$ 4,152		4,152		1,555
Accumulated other comprehensive loss \| Designated as Hedging Instrument \| Interest rate swaps
Derivatives, Fair Value [Line Items]
Unrealized (loss) gain resulting from changes in fair value of derivative instruments			(5,712)		(1,196)
Accumulated other comprehensive loss, interest rate swaps - tax provision			(112)		(112)
Accumulated other comprehensive loss			$ (5,824)		$ (1,308)