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DERIVATIVES AND RISK MANAGEMENT ACTIVITIES Table 2 (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Fair Value Hedges
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	$ (14,351)	$ 15,530	$ (14,710)	$ (2,450)
Amount of gain (loss) recognized in income on hedged item	13,736	(16,462)	13,898	1,868
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(615)	(932)	(812)	(582)
Fair Value Hedges | Interest rate swaps | Interest expense, net
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(19,573)	14,528	(17,345)	8,614
Amount of gain (loss) recognized in income on hedged item	19,573	(14,812)	17,345	(8,852)
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	(284)	0	(238)
Fair Value Hedges | Commodity contracts | Cost of product sales
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	5,222	1,002	2,635	(11,064)
Amount of gain (loss) recognized in income on hedged item	(5,837)	(1,650)	(3,447)	10,720
Amount of gain (loss) recognized in income on derivative (ineffective portion)	(615)	(648)	(812)	(344)
Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in OCI on derivative (effective portion)	(12,288)	(32,162)	(66,111)	(29,284)
Amount of gain (loss) reclassified from accumulated OCI into income (effective portion)	(9,147)	(1,225)	(16,914)	(1,225)
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	0	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)	(629)	0	(1,052)	0
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	0	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)	(16,749)	(15,708)	(13,451)	(12,830)
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)	(8,518)	(1,225)	(15,862)	(1,225)
Amount of gain (loss) recognized in income on derivative (ineffective portion)	0	0	4,010	0
Cash Flow Hedges | Commodity contracts | Other comprehensive income
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in OCI on derivative (effective portion)	4,461	(16,454)	(52,660)	(16,454)
Nondesignated Derivatives
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	20,091	4,433	16,283	(10,886)
Nondesignated Derivatives | Commodity contracts | Cost of product sales
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	28,255	4,462	23,937	(11,167)
Nondesignated Derivatives | Commodity contracts | Revenues
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative	(8,164)	(29)	(7,654)	235
Nondesignated Derivatives | Commodity contracts | Operating expenses
Derivative Instruments, Gain (Loss)
Amount of gain (loss) recognized in income on derivative				$ 46

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 amount of net gains and losses recognized in income during the period on derivative instruments designated and qualifying as hedging instruments in fair value hedges and related hedged items designated and qualifying in fair value hedges, on derivative instruments designated and qualifying as hedging instruments in cash flow hedges, and on derivative instruments not designated as hedging instruments.

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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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