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DERIVATIVES AND RISK MANAGEMENT ACTIVITIES Table 2 (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Fair Value Hedges
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	$ (65,411)	$ (30,664)	$ (29,600)
Amount of gain (loss) recognized in income on hedged item	63,592	41,389	42,173
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(1,819)	10,725	12,573
Fair Value Hedges | Interest rate swaps | Interest expense, net
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(55,183)	(27,443)	(6,661)
Amount of gain (loss) recognized in income on hedged item	54,588	27,443	6,661
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(595)	0	0
Fair Value Hedges | Commodity contracts | Cost of product sales
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(10,228)	(3,221)	(22,939)
Amount of gain (loss) recognized in income on hedged item	9,004	13,946	35,512
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(1,224)	10,725	12,573
Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in OCI on derivative (effective portion)	(53,452)	33,560
Amount of gain (loss) reclassified from accumulated OCI into income (effective portion)	5,030	(1,680)
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(4,010)	0
Cash Flow Hedges | Interest rate swaps | Interest expense, net
Derivative Instruments, Gain (Loss)
Amount of gain (loss) reclassified from accumulated OCI into income (effective portion)	0	0
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	0
Cash Flow Hedges | Interest rate swaps | Other comprehensive income
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in OCI on derivative (effective portion)	(84,199)	35,000
Cash Flow Hedges | Commodity contracts | Cost of product sales
Derivative Instruments, Gain (Loss)
Amount of gain (loss) reclassified from accumulated OCI into income (effective portion)	5,030	(1,680)	0
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(4,010)	0	0
Cash Flow Hedges | Commodity contracts | Other comprehensive income
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in OCI on derivative (effective portion)	30,747	(1,440)	(240)
Nondesignated Derivatives
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(4,173)	(3,102)	(17,183)
Nondesignated Derivatives | Commodity contracts | Cost of product sales
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(4,454)	(3,050)	(13,594)
Nondesignated Derivatives | Commodity contracts | Revenues
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	235
Nondesignated Derivatives | Commodity contracts | Operating expenses
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	$ 46	$ (52)	$ (3,589)

X

- Definition

The amount of net gains and losses recognized in income during the period on the hedged items related to derivative instruments designated and qualifying as hedging instruments in fair value hedges.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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The effective portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments that was recognized in other comprehensive income during the current period.

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