DERIVATIVE INSTRUMENTS DERIVATIVE INSTRUMENTS 3 (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Commodity Contract [Member]
Offsetting Derivative Assets [Abstract]
Gross amounts of recognized assets/liabilities	$ 2,190		$ 1,500
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	2,190		1,500
Gross amounts not offset in the balance sheet, Financial Instruments	(466)	[1]	(155)	[1]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		(498)
Net amount	1,724		847
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	(466)		(759)
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	(466)		(759)
Gross amounts not offset in the balance sheet, Financial Instruments	466	[2]	155	[2]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		0
Net amount	0		(604)
Interest Rate Contract [Member]
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	(4,735)		(3,735)
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	(4,735)		(3,735)
Gross amounts not offset in the balance sheet, Financial Instruments	0		0
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		0
Net amount	$ (4,735)		$ (3,735)

[1] The balances at March 31, 2014 and December 31, 2013 were related to derivative liabilities which can be net settled against derivative assets.

[2] The balances at March 31, 2013 and December 31, 2013 were related to derivative assets which can be net settled against derivative liabilities.