Fair Value Measurements

9 Months Ended

Sep. 30, 2012

Fair Value Disclosures [Abstract]

Fair Value Measurements

Fair Value Measurements

The Company reports certain assets and liabilities at fair value, which is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date (exit price). Under the accounting guidance for fair value measurements, inputs used to measure fair value are classified in one of three levels:

Level 1: Quoted market prices in active markets for identical assets or liabilities.

Level 2: Observable market-based inputs or unobservable inputs that are corroborated by market data.

Level 3: Unobservable inputs that are not corroborated by market data.

The following tables summarize, by level within the fair value hierarchy, the Company’s assets and liabilities that were accounted for at fair value on a recurring basis:

	September 30, 2012
	Level 1		Level 2			Total
Derivative instruments
Risk management assets - Commodity forward contracts	$	1,213	$	8,630		$	9,843
Risk management liabilities - Commodity forward contracts	—		(2,892		)	(2,892		)
Firm commitments
Hedged portion of firm commitment	—		1,019			1,019
Hedged portion of firm commitment	—		(8,630		)	(8,630		)
	December 31, 2011
	Level 1		Level 2			Total
Derivative instruments
Risk management assets - Commodity forward contracts	$	1,090	$	1,347		$	2,437
Risk management liabilities - Commodity forward contracts	—		(4,235		)	(4,235		)
Firm commitments
Hedged portion of firm commitment	—		3,262			3,262
Marketable securities
Available-for-sale equity securities	30,113		—			30,113

The Level 2 measurements are derived using forward curves supplied by industry recognized and unrelated third-party services. There were no transfers in and out of Levels 1 and 2 of the fair value hierarchy for the nine months ended September 30, 2012 and 2011.

In addition to the financial assets and liabilities above, the Company has other financial assets and liabilities subject to fair value measures. These financial assets and liabilities include cash and cash equivalents, accounts receivable, net, accounts payable and long-term debt, all of which are recorded at carrying value. The carrying amounts reported in the consolidated balance sheets for cash and cash equivalents, accounts receivable, net and accounts payable approximate their fair value due to the short maturities of these instruments. The carrying and fair values of the Company’s long-term debt are summarized in the table below. The Company’s long-term debt instruments are publicly-traded. A market approach, based upon quotes from financial reporting services, is used to measure the fair value of the Company’s long-term debt. Because the Company’s long-term debt instruments may not be actively traded, the inputs used to measure the fair value of the Company’s long-term debt are classified as Level 2 inputs within the fair value hierarchy.

	September 30, 2012				December 31, 2011
	Carrying Value		Fair Value		Carrying Value		Fair Value
6 5/8% senior notes due 2016	$	—	$	—	$	249,674	$	254,890
3.60% senior notes due 2022	248,842		253,738		—		—
6 1/2% senior notes due 2029	100,000		115,619		100,000		108,834
6 3/4% senior notes due 2032	250,000		288,515		250,000		263,988
6 1/2% GO Zone Senior Notes Due 2035	89,000		103,031		89,000		93,090
6 1/2% IKE Zone Senior Notes Due 2035	65,000		75,247		65,000		67,987
Loan related to tax-exempt waste disposal revenue    bonds due 2027	10,889		10,889		10,889		10,889