DERIVATIVE FINANCIAL INSTRUMENTS AND HEDGING ACTIVITIES - AOCI (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	$ 909,507	$ 624,485	$ 617,275	$ 626,705
Other comprehensive income before reclassifications	0	560	0	1,759
Amounts reclassified from accumulated other comprehensive income (loss)	0	(153)	(1,806)	(169)
Net current period other comprehensive income	0	407	(1,806)	1,590
Ending balance	966,260	624,440	966,260	624,440
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning balance	0	2,814	1,806	1,631
Ending balance	$ 0	$ 3,221	$ 0	$ 3,221

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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