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The impact on earnings of derivatives contract settlements associated with senior notes principal repayments during the period.

No definition available.

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To reclassify the impact on earnings of derivatives contract settlements associated with senior notes principal repayments during the period to Financing Activities.

No definition available.

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No definition available.

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Amount of noncash expense included in interest expense to issue debt and obtain financing associated with the related debt instruments. Alternate captions include noncash interest expense.

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Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

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Amount of cash paid during the period to settle an asset retirement obligation. Amounts paid to settle an asset retirement obligation are generally included in the operating section of the Statement of Cash Flows.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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Amount of increase (decrease) in cash and cash equivalents. Cash and cash equivalents are the amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Includes effect from exchange rate changes.

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Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations.

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The effect of exchange rate changes on cash balances in continuing operations held in foreign currencies.

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Amount of gain (loss) on sale or disposal of assets, including but not limited to property plant and equipment, intangible assets and equity in securities of subsidiaries or equity method investee.

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The increase (decrease) during the reporting period of all assets and liabilities used in operating activities.

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Amount of cash inflow (outflow) of financing activities, excluding discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

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No definition available.

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Amount of cash inflow (outflow) of investing activities, excluding discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

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No definition available.

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Amount of cash inflow (outflow) from operating activities, excluding discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

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No definition available.

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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The net cash outflow or inflow from other investing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of cash outflow in the form of ordinary dividends to common shareholders of the parent entity.

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Name:	us-gaap_PaymentsOfDividendsCommonStock
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The cash outflow to purchase long lived physical asset for use in the normal oil and gas operations and to purchase mineral interests in oil and gas properties not intended for resale.

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The cash outflow associated with the acquisition of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale; includes cash outflows to pay for construction of self-constructed assets.

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The cash inflow from the additional capital contribution to the entity.

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The net cash inflow or outflow from other financing activities. This element is used when there is not a more specific and appropriate element in the taxonomy.

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Amount of cash inflow (outflow) from long-term debt supported by a written promise to pay an obligation.

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The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period.

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Name:	us-gaap_ProceedsFromSaleAndMaturityOfMarketableSecurities
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The cash inflow to dispose of long-lived, physical assets and mineral interests in oil and gas properties used for normal oil and gas operations.

Name:	us-gaap_ProceedsFromSaleOfOilAndGasPropertyAndEquipment
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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Depreciation, depletion, amortization, and accretion related to oil and gas producing activities.

No definition available.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

Name:	us-gaap_ShareBasedCompensation
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.