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The discount factor used in the computation of the SEC full cost ceiling test that determines the limit of property acquisition, exploration and development costs that can be capitalized each period.

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Greenhouse Gas Emissions Reductions, Performance Cycle

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Relative Shareholder Return, Performance Cycle

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Return On Capital, Performance Cycle

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Summary Of Significant Accounting Policies [Line Items]

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 260
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 1
-Subparagraph (c)
-Publisher FASB
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The sum of the capitalized costs incurred during the period of unproved properties excluded from amortization including acquisition costs, exploration costs, development costs, and production costs.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 932
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-Name Accounting Standards Codification
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Net amount of capitalized costs relating to oil and gas producing activities.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 932
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The quantified amount of the future effect on cash flows.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 420
-SubTopic 10
-Section S99
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Carrying amount as of the balance sheet date of natural gas stored underground in depleted gas reservoirs, aquifers, or salt caverns to meet seasonal and peak load demands, and also as insurance against unforeseen supply disruptions, and deemed to be a current asset because it is expected to be used within twelve months or in the normal operating cycle.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-Name Accounting Standards Codification
-Section 50
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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