FAIR VALUE MEASUREMENTS (Tables)

3 Months Ended

Mar. 31, 2014

Fair Value Disclosures [Abstract]

Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis

The tables below present information about the Company's financial assets and liabilities measured and recorded at fair value on a recurring basis and indicate the fair value hierarchy of the inputs utilized to determine the fair values as of March 31, 2014 and December 31, 2013.

We have elected to offset the fair value amounts recognized for multiple derivative contracts executed with the same counterparty; however, fair value amounts by hierarchy level are presented on a gross basis in the tables below. We have posted cash margin with various counterparties to support hedging and trading activities. The cash margin posted is required by counterparties as collateral deposits and cannot be offset against the fair value of open contracts except in the event of default. We have no derivative contracts that are subject to master netting arrangements that are reflected gross on the balance sheet.

	As of March 31, 2014
	Fair Value Hierarchy						Total Gross Fair Value		Effect of Counter-party Netting			Net Carrying Value on Balance Sheet
	Level 1		Level 2		Level 3
Assets:
Money market funds	$	155,861	$	—	$	—	$	155,861	N/A			$	155,861
Non-qualified pension plan assets	4,955		—		—		4,955		N/A			4,955
Commodity contracts	33,436		19,839		800		54,075		(26,124		)	27,951
Derivatives included with intermediation agreement obligations	—		20,829		—		20,829		—			20,829
Derivatives included with inventory supply arrangement obligations	—		2,473		—		2,473		—			2,473
Total	$	194,252	$	43,141	$	800	$	238,193	$	(26,124	)	$	212,069
Liabilities:
Catalyst lease obligations	—		55,090		—		55,090		N/A			55,090
Commodity contracts	—		21,573		4,551		26,124		(26,124		)	—
Total	$	—	$	76,663	$	4,551	$	81,214	$	(26,124	)	$	55,090

	As of December 31, 2013
	Fair Value Hierarchy						Total
	Level 1		Level 2		Level 3
Assets:
Money market funds	$	5,857	$	—	$	—	$	5,857
Non-qualified pension plan assets	4,905		—		—		4,905
Commodity contracts	4,252		6,681		—		10,933
Derivatives included with inventory intermediation agreement obligations	—		6,016		—		6,016
Liabilities:
Commodity contracts	—		6,989		23,365		30,354
Catalyst lease obligations	—		53,089		—		53,089
Derivatives included with inventory supply arrangement obligations	—		177		—		177

Schedule of Effect of Significant Unobservable Inputs

The table below summarizes the changes in fair value measurements of commodity contracts categorized in Level 3 of the fair value hierarchy:

	Three Months Ended March 31,
	2014			2013
Balance at beginning of period	$	(23,365	)	$	—
Purchases	—			—
Settlements	(1,305		)	—
Unrealized gain included in earnings	20,919			—
Transfers into Level 3	—			—
Transfers out of Level 3	—			—
Balance at end of period	$	(3,751	)	$	—

Schedule of Fair value of Debt

The table below summarizes the fair value and carrying value as of March 31, 2014 and December 31, 2013.

	March 31, 2014				December 31, 2013
	Carrying value		Fair  value		Carrying  value		Fair value
Senior secured notes (a)	$	667,738	$	698,785	$	667,487	$	697,568
Revolver (b)	—		—		15,000		15,000
Catalyst leases (c)	55,090		55,090		53,089		53,089
	722,828		753,875		735,576		765,657
Less - Current maturities	12,491		12,491		12,029		12,029
Long-term debt	$	710,337	$	741,384	$	723,547	$	753,628

(a) The estimated fair value, categorized as a Level 2 measurement, was calculated based on the present value of future expected payments utilizing implied current market interest rates based on quoted prices of the senior secured notes.

(b) The estimated fair value approximates carrying value, categorized as a Level 2 measurement, as these borrowings bear interest based upon short-term floating market interest rates.

(c) Catalyst leases are valued using a market approach based upon commodity prices for similar instruments quoted in active markets and are categorized as a Level 2 measurement.