The fair value of financial assets and financial liabilities at March 31, 2012, is shown in the table below:

	Fair Value Measurements
	March 31, 2012
	Level 2		Level 3		Netting Adjustments			Total
	(in millions)
Financial Assets
Commodity derivative instruments - short-term	$	347.5	$	-	$	(13.7	)	$	333.8
Commodity derivative instruments - long-term		115.8		-		(0.2	)		115.6
Total financial assets	$	463.3	$	-	$	(13.9	)	$	449.4

Financial Liabilities
Commodity derivative instruments - short-term	$	11.6	$	2.1	$	(13.7	)	$	-
Commodity derivative instruments - long-term		0.3		-		(0.2	)		0.1
Total financial liabilities	$	11.9	$	2.1	$	(13.9	)	$	0.1

The fair value of financial assets and financial liabilities at December 31, 2011, is shown in the table below:

	Fair Value Measurements
	December 31, 2011
	Level 2		Level 3		Netting Adjustments			Total
	(in millions)
Financial Assets
Commodity derivative instruments - short-term	$	284.1	$	-	$	(10.4	)	$	273.7
Commodity derivative instruments - long-term		123.5		-		-			123.5
Total financial assets	$	407.6	$	-	$	(10.4	)	$	397.2

Financial Liabilities
Commodity derivative instruments - short-term	$	11.7	$	-	$	(10.4	)	$	1.3
Commodity derivative instruments - long-term		-		-		-			-
Total financial liabilities	$	11.7	$	-	$	(10.4	)	$	1.3

- Definition

This element represents the disclosure related to assets and liabilities by class, including [financial] instruments measured at fair value that are classified in stockholders' equity, if any, that are measured at fair value on a recurring and/or nonrecurring basis in periods after initial recognition (for example, impaired assets). The disclosures that may be required or desired include: (a) the fair value measurements recorded during the period and the reasons for the measurements and (b) the level within the fair value hierarchy in which the fair value measurements in their entirety fall, segregating fair value measurements using quoted prices in active markets for identical assets or liabilities (Level 1), significant other observable inputs (Level 2), and significant unobservable inputs (Level 3). Where the quoted price in an active market for the identical liability is not available, the Level 1 input is the quoted price of an identical liability when traded as an asset.

+ References

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- Definition

Tabular disclosure of the fair value measurement of assets using significant unobservable inputs (Level 3), a reconciliation of the beginning and ending balances, separately presenting changes during the period attributable to the following: (1) total gains or losses for the period (realized and unrealized), segregating those gains or losses included in earnings (or changes in net assets) and gains or losses recognized in other comprehensive income, and a description of where those gains or losses included in earnings (or changes in net assets) are reported in the statement of income (or activities); (2) purchases, sales, issuances, and settlements (each type disclosed separately); and (3) transfers in and transfers out of Level 3 (for example, transfers due to changes in the observability of significant inputs), by class of asset.

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- Definition

Tabular disclosure of the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments, assets, and liabilities. Such certain disclosures about the financial instruments, assets, and liabilities include: (1) the fair value of the required items together with their carrying amounts (as appropriate) and (2) the methodology and assumptions used in developing such estimates of fair value.

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