Debt Instrument, Covenant Compliance, Loan Limit Percentage

No definition available.

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- Definition

Debt Instrument, Covenant Compliance, Maximum Debt To Earnings Before Interest, Expense, Income Taxes, Depreciation, Depletion, Amortization And Exploration Expenses, Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant Compliance, Minimum Current Assets To Current Liabilities, Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant Compliance, Minimum Net Present Value Of Proved Reserves To Consolidated Debt, Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Cross Default Provision, Minimum Threshold Amount

+ References

No definition available.

+ Details

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- Definition

Line of Credit, Cross Default Provision, Minimum Threshold Amount

+ References

No definition available.

+ Details

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.8)

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 8

-Article 5

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 8

-Article 9

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 45

-Paragraph 2

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-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

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+ Details

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Balance Type:	credit
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- Details

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of interest capitalized during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Allowance for Funds Used during Construction

-URI http://asc.fasb.org/extlink&oid=6504829

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

+ Details

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- Definition

Amount of the cost of borrowed funds accounted for as interest expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.9)

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 9

-Article 9

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.19(b),22(b))

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 19, 22

-Article 5

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Details

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Long-Term Debt and Notes Payable (Additional Information) (Details) (USD $)	12 Months Ended			0 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Sep. 02, 2014	Oct. 30, 2012	Nov. 17, 2014
Debt Instrument [Line Items]
Cross default provision, minimum threshold amount	$ 10,000,000
Credit facility, current borrowing capacity	2,000,000,000	1,250,000,000
Loan limit percentage (less than)	10.00%
Cross default provision, minimum debt default amount	75,000,000
Interest expense	37,771,000us-gaap_InterestExpense	39,736,000us-gaap_InterestExpense	47,565,000us-gaap_InterestExpense
Amortization of debt issuance costs	5,700,000us-gaap_AmortizationOfFinancingCosts	2,000,000us-gaap_AmortizationOfFinancingCosts	2,400,000us-gaap_AmortizationOfFinancingCosts
Interest expense, capitalized	200,000us-gaap_InterestCostsCapitalized	200,000us-gaap_InterestCostsCapitalized	500,000us-gaap_InterestCostsCapitalized
Unused capacity, commitment fee percentage	30.00%
Senior Term Loans \| Senior Term Loans, (floating rate interest LIBOR plus 1.625%)
Debt Instrument [Line Items]
Long-term debt		600,000,000
Syndicated Credit Facility \| Credit Facility, September 2, 2014
Debt Instrument [Line Items]
Credit facilities				1,500,000,000		2,000,000,000
Debt instrument, term				5 years
Credit facility, current borrowing capacity				2,100,000,000
Debt covenant, debt to EBITDAX ratio	4.0
Debt covenant, current assets to current liabilities ratio	1.0
Debt covenant, minimum net present value of proved reserves to consolidated debt, ratio	1.50
Syndicated Credit Facility \| Credit Facility, October 30, 2012
Debt Instrument [Line Items]
Credit facilities					$ 1,250,000,000
Debt instrument, term					5 years