DERIVATIVE INSTRUMENTS - Effect of Interest Rate Swaps on Consolidated Statements of Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net interest component of interest rate swaps	$ 31,475	$ (96,470)	$ (16,685)	$ (200,626)
Realized gains (losses) on termination or maturity of interest rate swaps	0	(58)	834	(58)
Unrealized gains (losses) on interest rate swaps	$ 343,475	$ (177,567)	$ 1,320,760	$ (28,383)

The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Name:	us-gaap_UnrealizedGainLossOnDerivatives
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration