DERIVATIVE INSTRUMENTS - Effect of Derivative Instruments Designated Cash Flow Hedges on Statements of Operations (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	$ 1,397,030	$ 998,440	$ 1,375,796	$ 962,306
Balance, End of Period	1,420,951	1,341,905	1,420,951	1,341,905
Accumulated Other Comprehensive Income (Loss)
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	(56,679)	(1,663)	(45,443)	(23,807)
Balance, End of Period	(68,700)	(25,306)	(68,700)	(25,306)
Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Roll Forward]
Amount of Gain (Loss) Recognized in AOCI	(27,679)	19,335	(25,874)	27,314
Amount of Gain (Loss) Reclassified from AOCI into Earnings	400	13,394	9,314	8,351
Designated as Hedging Instrument \| Accumulated Other Comprehensive Income (Loss)
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	(13,312)	8,511	(6,203)	(4,512)
Balance, End of Period	(41,391)	14,452	(41,391)	14,452
Designated as Hedging Instrument \| Interest rate swap \| Cash Flow Hedges \| Interest expense
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	(16,678)	16,188	619	592
Amount of Gain (Loss) Recognized in AOCI	(25,163)	6,306	(41,053)	21,247
Amount of Gain (Loss) Reclassified from AOCI into Earnings	1,320	150	2,727	(505)
Balance, End of Period	(43,161)	22,344	(43,161)	22,344
Designated as Hedging Instrument \| Cross-currency swap \| Cash Flow Hedges \| Other income, net
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	(3,895)	(7,677)	(6,190)	(5,104)
Amount of Gain (Loss) Recognized in AOCI	(1,716)	13,029	5,757	6,067
Amount of Gain (Loss) Reclassified from AOCI into Earnings	(3,327)	13,244	1,851	8,856
Balance, End of Period	(2,284)	$ (7,892)	(2,284)	$ (7,892)
Designated as Hedging Instrument \| Cross-currency swap \| Net Investment Hedges \| Interest income
Derivative Instruments, Gain (Loss) [Roll Forward]
Balance, Beginning of Period	7,261		(632)
Amount of Gain (Loss) Recognized in AOCI	(800)		9,422
Amount of Gain (Loss) Reclassified from AOCI into Earnings	2,407		4,736
Balance, End of Period	$ 4,054		$ 4,054

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

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- Definition

Amount, before tax and reclassification, of gain (loss) from derivative instrument designated and qualifying cash flow hedge included in assessment of hedge effectiveness.

+ References

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- Definition

Amount, after tax, of reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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