Fair Value Measurements

9 Months Ended

Sep. 30, 2011

Fair Value Measurements [Abstract]

Fair Value Measurements

9. 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, 2011
	Level 1		Level 2			Total
Derivative instruments
Risk management assets	$	365	$	2,829		$	3,194
Risk management liabilities		—		(3,506	)		(3,506	)
Firm commitments
Hedged portion of firm commitment		—		1,780			1,780
Marketable securities
Available-for-sale investments		21,218		—			21,218

	December 31, 2010
	Level 1			Level 2		Total
Derivative instruments
Risk management assets	$	47		$	—	$	47
Risk management liabilities		(46	)		—		(46	)

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, 2011 and 2010.

In addition to the financial instruments 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 below:

	September 30, 2011				December 31, 2010
	Carrying Value		Fair Value		Carrying Value		Fair Value
6 5/8% senior notes due 2016	$	249,654	$	256,875	$	249,593	$	258,438
6   1/2% senior notes due 2029		100,000		106,823		100,000		99,875
6   3/4% senior notes due 2032		250,000		257,718		250,000		251,925
2035 GO Zone 6  1/2% Notes		89,000		92,073		89,000		88,653
2035 IKE Zone 6  1/2% Notes		65,000		67,244		65,000		64,905
Variable rate tax-exempt waste disposal revenue bonds due 2027		10,889		10,889		10,889		10,889