Derivative Instruments (Tables)

6 Months Ended

Jun. 30, 2012

Derivative Instruments

Derivatives designated and not designated as hedging instruments

		Three Months Ended						Six Months Ended
		June 30,						June 30,
		2012			2011			2012			2011
	(Thousands)
Commodity derivatives designated as cash flow hedges
Amount of (loss) gain recognized in other comprehensive income (OCI) (effective portion), net of tax		$	(8,930	)	$	33,253		$	98,558		$	37,453
Amount of gain reclassified from accumulated OCI into operating revenues (effective portion), net of tax		$	55,286		$	9,919		$	103,272		$	26,823
Amount of (loss) gain recognized in operating revenues (ineffective portion) (a)		$	(212	)	$	364		$	(243	)	$	(261	)
Interest rate derivatives designated as cash flow hedges
Amount of (loss) gain recognized in OCI (effective portion), net of tax		$	(6,670	)	$	—		$	(4,297	)	$	—
Amount of loss reclassified from accumulated OCI into interest expense (effective portion), net of tax		$	(64	)	$	(29	)	$	(129	)	$	(58	)
Commodity derivatives designated as fair value hedges (b)
Amount of (loss) gain recognized in operating revenues for fair value commodity contracts		$	(2,378	)	$	1,363		$	4,694		$	(533	)
Fair value gain (loss) recognized in operating revenues for inventory designated as hedged item		$	8,388		$	60		$	(1,543	)	$	1,693
Derivatives not designated as hedging instruments
Amount of (loss) gain recognized in operating revenues		$	(790	)	$	856		$	1,673		$	(823	)

(a)No amounts have been excluded from effectiveness testing of cash flow hedges.

(b)For the three months ended June 30, 2012, the net impact on operating revenues consisted of a $6.0 million gain related to the exclusion of the spot/forward differential from the assessment of effectiveness. For the three months ended June 30, 2011, the net impact on operating revenues consisted of a $2.1 million gain related to the exclusion of the spot/forward differential from the assessment of effectiveness and a $0.7 million loss due to changes in basis. For the six months ended June 30, 2012, the net impact on operating revenues consisted of a $2.8 million gain due to the exclusion of the spot/forward differential from the assessment of effectiveness and a $0.4 million gain due to changes in basis. For the six months ended June 30, 2011, the net impact on operating revenues consisted of a $1.5 million gain related to the exclusion of the spot/forward differential from the assessment of effectiveness and a $0.3 million loss due to changes in basis.

Asset and liability derivatives

		June 30,		December 31,
		2012		2011
	(Thousands)
Asset derivatives
Commodity derivatives designated as hedging instruments		$	392,437	$	412,626
Commodity derivatives not designated as hedging instruments		75,150		99,535
Total asset derivatives		$	467,587	$	512,161
Liability derivatives
Commodity derivatives designated as hedging instruments		$	8,014	$	3,681
Interest rate derivatives designated as hedging instruments		18,374		10,861
Commodity derivatives not designated as hedging instruments		82,826		108,764
Total liability derivatives		$	109,214	$	123,306