v2.4.0.8

Derivatives (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
Derivatives, Fair Value [Line Items]
Commodity derivative assets	$ 147,983	$ 31,055	$ 38,352
Commodity derivative liabilities	0	0	0
Commodity derivative assets - current	126,396	71,319	105,390
Commodity derivative assets - noncurrent	2,383	246	5
Commodity derivative liabilities - current	(229,265)	(63,954)	(88,234)
Commodity derivative liabilities - noncurrent	(26,203)	(6,644)	(9,636)
Commodity
Derivatives, Fair Value [Line Items]
Commodity derivative assets	218,236	70,870	92,519
Commodity derivative liabilities	(265,214)	(85,383)	(112,095)
Cash collateral	(79,711)	15,480	27,101
Total	(126,689)	967	7,525
Commodity | Commodity derivative assets - current
Derivatives, Fair Value [Line Items]
Commodity derivative assets	212,760	69,289	89,540
Commodity derivative liabilities	(6,653)	(13,450)	(11,251)
Cash collateral	(79,711)	15,480	27,101
Commodity derivative assets - current	126,396	71,319	105,390
Commodity | Commodity derivative assets - noncurrent
Derivatives, Fair Value [Line Items]
Commodity derivative assets	2,383	246	5
Commodity derivative liabilities	0	0	0
Cash collateral	0	0	0
Commodity derivative assets - noncurrent	2,383	246	5
Commodity | Commodity derivative liabilities - current
Derivatives, Fair Value [Line Items]
Commodity derivative assets	2,897	1,286	2,933
Commodity derivative liabilities	(232,162)	(65,240)	(91,167)
Cash collateral	0	0	0
Commodity derivative liabilities - current	(229,265)	(63,954)	(88,234)
Commodity | Commodity derivative liabilities - noncurrent
Derivatives, Fair Value [Line Items]
Commodity derivative assets	196	49	41
Commodity derivative liabilities	(26,399)	(6,693)	(9,677)
Cash collateral	0	0	0
Commodity derivative liabilities - noncurrent	$ (26,203)	$ (6,644)	$ (9,636)

X

- Definition

Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer.

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Carrying amount as of the balance sheet date of the asset arising from commodity contracts such as futures contracts tied to the movement of a particular commodity, which are expected to be converted into cash or otherwise disposed of after a year or beyond the normal operating cycle, if longer.

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Amount of right to receive cash collateral under master netting arrangements that have not been offset against derivative liabilities.

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The net amount as of the balance sheet date of the fair value of derivative assets and derivative liabilities that in accordance with the entity's accounting policy were offset against collateral under a master netting arrangement.

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Fair value before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset.

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