The amount of the capitalized interest incurred during the period of unproved properties excluded from amortization.

No definition available.

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 932

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-10.(c)(7)(ii))

-URI http://asc.fasb.org/extlink&oid=27015464&loc=d3e511914-122862

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 10

-Paragraph c

-Subparagraph 3(ii)(A)

-Article 4

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- Definition

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.

+ References

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- Definition

The capitalized costs incurred during the period (excluded from amortization) in identifying areas that may warrant examination and in examining specific areas that are considered to have prospects of containing oil and gas reserves, including costs of drilling exploratory wells and exploratory-type stratigraphic test wells. Exploration costs may be incurred both before acquiring the related property (sometimes referred to in part as prospecting costs) and after acquiring the property. Principal types of exploration costs, which include depreciation and applicable operating costs of support equipment and facilities and other costs of exploration activities, are: costs of topographical, geographical and geophysical studies, rights of access to properties to conduct those studies, and salaries and other expenses of geologists, geophysical crews, and others conducting those studies. Collectively, these are sometimes referred to as geological and geophysical or "G&G" costs. Exploration costs also include costs of carrying and retaining undeveloped properties, such as delay rentals, ad valorem taxes on properties, legal costs for title defense, the maintenance of land and lease records, dry hole contributions and bottom hole contributions, costs of drilling and equipping exploratory wells and costs of drilling exploratory-type stratigraphic test wells.

+ References

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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

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Oil and Gas Reserves (Unaudited): Unproved Properties Excluded from Amortization (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Leasehold acquisition cost	$ 70,201,000us-gaap_AcquisitionCosts
Exploration cost	34,166,000us-gaap_ExplorationCosts
Capitalized interest	5,128,000
Total	109,495,000
Current Year [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Leasehold acquisition cost	16,077,000
Exploration cost	23,954,000
Capitalized interest	207,000
Total	40,238,000
Prior Year [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Leasehold acquisition cost	4,889,000
Exploration cost	10,212,000
Capitalized interest	748,000
Total	15,849,000
More Than One Year, Less Than Two Years Prior [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Leasehold acquisition cost	35,823,000
Exploration cost	0
Capitalized interest	360,000
Total	36,183,000
More Than Two Years Prior [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Leasehold acquisition cost	13,412,000
Exploration cost	0
Capitalized interest	3,813,000
Total	17,225,000
Oil and Gas [Member]
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]
Interest Costs, Capitalized During Period	$ 1,000,000	$ 1,100,000	$ 700,000