USE OF DERIVATIVES, OFFSETTING DISCLOSURES AND CHANGES IN OTHER COMPREHENSIVE INCOME BY COMPONENT- Offsetting Assets (Details) - USD ($) $ in Thousands		Mar. 31, 2016	Dec. 31, 2015
Offsetting of derivative assets [Abstract]
Gross Amounts of Recognized Assets		$ 802	$ 7,720
Net Amounts of Assets Presented in the Balance Sheet		56,241	29,283
Cash Collateral Received		(72,037)	(50,193)
Offsetting Derivatives Assets [Member]
Offsetting of derivative assets [Abstract]
Gross Amounts of Recognized Assets		464	4,758
Gross Amounts Offset in the Balance Sheet		338	2,962
Net Amounts of Assets Presented in the Balance Sheet		802	7,720
Financial Instruments	[1]	(802)	(7,720)
Cash Collateral Received	[1]	0	0
Net Amount		0	0
Offsetting Derivatives Assets [Member] | Counterparty 2 [Member]
Offsetting of derivative assets [Abstract]
Gross Amounts of Recognized Assets			0
Gross Amounts Offset in the Balance Sheet			23
Net Amounts of Assets Presented in the Balance Sheet			23
Financial Instruments	[1]		(23)
Cash Collateral Received	[1]		0
Net Amount			0
Offsetting Derivatives Assets [Member] | Counterparty 4 [Member]
Offsetting of derivative assets [Abstract]
Gross Amounts of Recognized Assets		464	4,758
Gross Amounts Offset in the Balance Sheet		338	2,939
Net Amounts of Assets Presented in the Balance Sheet		802	7,697
Financial Instruments	[1]	(802)	(7,697)
Cash Collateral Received	[1]	0	0
Net Amount		$ 0	$ 0

[1] Amounts presented are limited to recognized liabilities and cash collateral received associated with the indicated counterparty sufficient to reduce the related Net Amount to zero in accordance with ASU No. 2011-11, as amended by ASU No. 2013-01.