USE OF DERIVATIVES, OFFSETTING DISCLOSURES AND CHANGES IN OTHER COMPREHENSIVE INCOME BY COMPONENT - Components of Income Statement and Other Comprehensive Income (Details) - USD ($) $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Income statement-related [Abstract]
Amount of gain reclassified from Accumulated other comprehensive income (loss)		$ (2,702)	$ (11,162)	$ (19,624)	$ (25,776)
Amortization of unrealized gain, net of unrealized losses on de-designated Derivatives				12,854
Realized and unrealized (loss) gain on non-designated Derivatives (net)		(9,221)		(105,720)
Other comprehensive income (loss)-related [Abstract]
Amount of (loss) gain recognized in Other comprehensive income		(7,648)	7,580	(22,945)	46,385
Interest Rate Swap Agreements [Member]
Income statement-related [Abstract]
Realized and unrealized (loss) gain on non-designated Derivatives (net)		(10,262)		(106,761)
Eurodollar Futures Contract [Member]
Income statement-related [Abstract]
Realized and unrealized (loss) gain on non-designated Derivatives (net)		1,041		1,041
Interest Expense [Member]
Income statement-related [Abstract]
Decrease in interest expense and increase in Net (loss) income as a result of the use of Derivatives		2,702	11,162	19,624	25,776
Interest Expense [Member] | Secured Borrowings [Member]
Income statement-related [Abstract]
Amount of gain reclassified from Accumulated other comprehensive income (loss)			11,585	7,891	27,277
Amortization of unrealized gain, net of unrealized losses on de-designated Derivatives		3,120		12,854
Decrease in interest expense and increase in Net (loss) income as a result of the use of Derivatives	[1]	3,120	11,585	20,745	27,277
Interest Expense [Member] | Unsecured Borrowings [Member]
Income statement-related [Abstract]
Amount of gain reclassified from Accumulated other comprehensive income (loss)		$ (418)	$ (423)	$ (1,121)	$ (1,501)

[1] Included in “Interest expense:  Secured borrowings” on the face of the Statements of Operations.