Derivative Instruments (Details 2) $ in Thousands	Sep. 30, 2015 USD ($) item	Dec. 31, 2014 USD ($)
Fair value of derivative instruments
Current portion of fair value of derivative assets	$ 834,482	$ 692,554
Noncurrent portion of fair value of derivative assets	2,007,828	899,997
Total asset derivatives	2,842,310	1,592,551
Derivatives not designated as hedges for accounting purposes \| Net fair value of commodity derivative assets position
Fair value of derivative instruments
Current portion of fair value of derivative assets	834,482	692,554
Noncurrent portion of fair value of derivative assets	2,007,828	899,997
Total asset derivatives	2,842,310	1,592,551
Net derivatives	$ 2,842,310	$ 1,592,551
Derivatives designated as hedges for accounting purposes
Fair value of derivative instruments
Number of derivative instruments held \| item	0

Fair value, after the 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. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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