Derivative Instruments and Hedging Activities (Tables)

12 Months Ended

Dec. 31, 2012

Table Text Block Supplement [Abstract]

Commodity derivative income (expense), included in our Consolidated Statements of Operations

The following is a summary of “Derivatives expense (income)” included in our Consolidated Statements of Operations:

	Year Ended December 31,
In thousands	2012			2011			2010
Oil
Payment on settlements of derivative contracts	$	9,991		$	25,128		$	93,417
Fair value adjustments to derivative contracts – income	(10,904		)	(58,980		)	(44,441		)
Total derivatives expense (income) – oil	(913		)	(33,852		)	48,976
Natural gas
Receipt on settlements of derivative contracts	(27,871		)	(27,505		)	(61,805		)
Fair value adjustments to derivative contracts – expense (income)	23,950			8,860			(8,585		)
Total derivatives expense (income) – natural gas	(3,921		)	(18,645		)	(70,390		)
Ineffectiveness on interest rate swaps	—			—			(2,419		)
Derivatives expense (income)	$	(4,834	)	$	(52,497	)	$	(23,833	)

Commodity derivative contracts not classified as hedging instruments

Commodity Derivative Contracts Not Classified as Hedging Instruments

					Contract Prices per Barrel
		Type of	Volume			Weighted Average Price
Year	Months	Contract	(Barrels per day)		Range	Floor		Ceiling
Oil Contracts:
2013	Jan – Mar	Collar	55,000	$	70.00 – 113.00	$	78.91	$	108.01
	Apr – June	Collar	56,000		75.00 – 121.50	79.64		108.61
	July – Sept	Collar	56,000		75.00 – 133.10	79.64		109.15
	Oct – Dec	Collar	54,000		80.00 – 127.50	80.00		117.53
2014	Jan – Mar	Collar	52,000	$	80.00 – 104.50	$	80.00	$	102.44
	Apr – June	Collar	52,000		80.00 – 104.50	80.00		102.44
	July – Sept	Collar	48,000		80.00 – 98.80	80.00		97.46
	Oct – Dec	Collar	48,000		80.00 – 98.80	80.00		97.46

Derivative financial instruments in Balance Sheet

At December 31, 2012 and 2011, we had derivative financial instruments recorded in our Consolidated Balance Sheets as follows:

		Estimated Fair Value Asset (Liability) December 31,
Type of Contract	Balance Sheet Location	2012			2011
		In thousands
Derivatives not designated as hedging instruments:
Derivative Assets
Crude oil contracts	Derivative assets – current	$	19,477		$	23,452
Natural gas contracts	Derivative assets – current	—			23,950
Crude oil contracts	Derivative assets – long-term	36			29
Derivative Liabilities
Crude oil contracts	Derivative liabilities – current	(2,659		)	(22,610		)
Deferred premiums (1)	Derivative liabilities – current	(183		)	(3,913		)
Crude oil contracts	Derivative liabilities – long-term	(23,781		)	(18,702		)
Deferred premiums (1)	Derivative liabilities – long-term	—			(170		)
Total derivatives not designated as hedging instruments		$	(7,110	)	$	2,036

(1) Deferred premiums payable relate to various oil floor contracts and are payable on a monthly basis through January 2013.