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Long-Term Debt (Narrative) (Details) (USD $) | 12 Months Ended | 9 Months Ended | 0 Months Ended |  |  |  |  |  |  |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012 | Sep. 30, 2013 | Dec. 27, 2013 | Aug. 18, 2014 | Dec. 21, 2012 | Oct. 17, 2012 | Oct. 09, 2012 | Mar. 31, 2011 | Apr. 23, 2014 | Apr. 22, 2014 | May 03, 2011 | Sep. 30, 2010 | Nov. 25, 2014 | Feb. 26, 2015
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest capitalized | $ 9,687,000 us-gaap_InterestCostsCapitalized |  | $ 7,132,000 us-gaap_InterestCostsCapitalized |  | $ 0 us-gaap_InterestCostsCapitalized |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest expense | 23,986,000 us-gaap_InterestExpense |  | 17,490,000 us-gaap_InterestExpense |  | 7,458,000 us-gaap_InterestExpense |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt covenant ratio for EBITDAX |  |  |  |  |  | 3.00 gpor_DebtInstrumentCovenantComplianceEarningsBeforeIncomeTaxDepreciationDepletionAmortizationAndExplorationExpensesRatio |  |  |  |  |  |  |  |  |  |  |  |  |
Long-tern debt | 701,826,000 us-gaap_LongTermDebt |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Unamortized discount | 2,800,000 us-gaap_DebtInstrumentUnamortizedDiscount |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  | 7.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  | 7.75%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |  |  |  |
Long-tern debt | 600,000,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | [1] | 300,000,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | [1] |  |  |  | 600,000,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | [1] |  |  |  |  |  |  |  |  |  |
Debt issued |  |  |  |  |  |  |  | 300,000,000.0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  | 50,000,000.0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | 250,000,000.0 us-gaap_DebtInstrumentCarryingAmount / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |
Redemption of principal amount plus aggregate net proceeds |  |  |  |  |  |  |  |  |  |  |  | 100.00%gpor_DebtInstrumentRedemptionPercentageOfPrincipalAmountPlusAggregateNetProceeds / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |
Discount issue price, price |  |  |  |  |  |  |  | 106.00%gpor_DebtInstrumentDiscountIssuePricePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  | 98.534%gpor_DebtInstrumentDiscountIssuePricePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |
Premium issue price, percent |  |  |  |  |  |  |  |  |  | 101.00%gpor_DebtInstrumentPremiumIssuePricePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |  |
Unamortized discount |  |  |  |  |  |  |  |  |  |  | 3,700,000 us-gaap_DebtInstrumentUnamortizedDiscount / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |
Effective interest rate |  |  |  |  |  |  |  | 6.561%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  | 7.531%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember | 8.00%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |
Unamortized premium |  |  |  |  |  |  |  | 18,000,000 us-gaap_DebtInstrumentUnamortizedPremium / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  | 500,000 us-gaap_DebtInstrumentUnamortizedPremium / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember |  |  |  |  |  |  |  |  |
Building Loans [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stated interest rate |  |  |  |  |  |  |  |  |  |  |  |  | 5.82%us-gaap_DebtInstrumentInterestRateStatedPercentage / us-gaap_LongtermDebtTypeAxis = gpor_BuildingLoansMember |  |  |  |  |  |
Long-tern debt | 1,826,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = gpor_BuildingLoansMember | [2] | 1,995,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = gpor_BuildingLoansMember | [2] |  |  |  |  |  |  |  |  | 2,400,000 us-gaap_LongTermDebt / us-gaap_LongtermDebtTypeAxis = gpor_BuildingLoansMember |  |  |  |  |  |
Loan, periodic payment |  |  |  |  |  | 22,000 us-gaap_DebtInstrumentPeriodicPayment / us-gaap_LongtermDebtTypeAxis = gpor_BuildingLoansMember |  |  |  |  |  |  |  |  |  |  |  |  |
Minimum [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of notes required to be outstanding for redemption |  |  |  |  |  |  |  |  |  |  |  | 65.00%gpor_DebtInstrumentOutstandingNotesRequiredForRedemption / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember / us-gaap_RangeAxis = us-gaap_MinimumMember |  |  |  |  |  |  |
Maximum [Member] | Senior Notes [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Redemption of principal amount plus aggregate net proceeds |  |  |  |  |  |  |  |  |  |  |  | 35.00%gpor_DebtInstrumentRedemptionPercentageOfPrincipalAmountPlusAggregateNetProceeds / us-gaap_LongtermDebtTypeAxis = us-gaap_SeniorNotesMember / us-gaap_RangeAxis = us-gaap_MaximumMember |  |  |  |  |  |  |
Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Revolving credit facility |  |  |  |  |  |  | 1,500,000,000.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  | 350,000,000.0 us-gaap_LineOfCreditFacilityMaximumBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |
Borrowing capacity |  |  |  |  |  |  | 150,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  | 275,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember | 150,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  | 50,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |
Debt instrument, description of rate | LIBOR01 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Nova Scotia, Amegy, KeyBank [Member] | Letter of Credit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  | 70,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember | 20,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |
Debt covenant ratio for EBITDAX |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2.00 gpor_DebtInstrumentCovenantComplianceEarningsBeforeIncomeTaxDepreciationDepletionAmortizationAndExplorationExpensesRatio / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |
Bank of Nova Scotia [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity | 450,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_BankofNovaScotiaMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Base Rate Loans [Member] | Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable rate, minimum |  |  |  |  |  |  | 0.50%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_DebtInstrumentAxis = gpor_BaseRateLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |
Applicable rate, maximum |  |  |  |  |  |  | 1.50%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_DebtInstrumentAxis = gpor_BaseRateLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |
Second Amendment of Restated Credit Agreement [Member] | Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity | 450,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Future borrowings available | 306,400,000 us-gaap_LineOfCreditFacilityRemainingBorrowingCapacity / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Second Amendment of Restated Credit Agreement [Member] | Nova Scotia, Amegy, KeyBank [Member] | Letter of Credit [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  | 125,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |
Debt covenant ratio for EBITDAX |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.50 gpor_DebtInstrumentCovenantComplianceEarningsBeforeIncomeTaxDepreciationDepletionAmortizationAndExplorationExpensesRatio / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |
Debt covenant ratio for future EBITDAX |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.25 gpor_DebtInstrumentCovenantComplianceFutureEarningsBeforeIncomeTaxDepreciationDepletionAmortizationandExplorationExpensesRatio / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |
Letters of Credit Outstanding, Amount | 43,600,000 us-gaap_LettersOfCreditOutstandingAmount / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Disposition costs, maximum expenses allowed | 3,000,000 gpor_DebtInstrumentDispositionCostsMaximumExpensesAllowed / us-gaap_CreditFacilityAxis = us-gaap_LetterOfCreditMember / us-gaap_DebtInstrumentAxis = gpor_SecondAmendmentofRestatedCreditAgreementMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Euro Dollar Loans [Member] | Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Applicable rate, minimum |  |  |  |  |  |  | 1.50%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMinimum / us-gaap_DebtInstrumentAxis = gpor_EuroDollarLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |
Applicable rate, maximum |  |  |  |  |  |  | 2.50%us-gaap_DebtInstrumentInterestRateStatedPercentageRateRangeMaximum / us-gaap_DebtInstrumentAxis = gpor_EuroDollarLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |
Effective interest rate | 1.91%us-gaap_DebtInstrumentInterestRateEffectivePercentage / us-gaap_DebtInstrumentAxis = gpor_EuroDollarLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Federal Funds Rate [Member] | Base Rate Loans [Member] | Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread |  |  |  |  |  |  | 0.50%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = gpor_BaseRateLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember / us-gaap_VariableRateAxis = gpor_FederalFundsRateMember |  |  |  |  |  |  |  |  |  |  |  |
Eurodollar [Member] | Base Rate Loans [Member] | Nova Scotia, Amegy, KeyBank [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Basis spread |  |  |  |  |  |  | 1.00%us-gaap_DebtInstrumentBasisSpreadOnVariableRate1 / us-gaap_DebtInstrumentAxis = gpor_BaseRateLoansMember / us-gaap_LineOfCreditFacilityAxis = gpor_NovaScotiaAmegyKeybankMember / us-gaap_VariableRateAxis = us-gaap_EurodollarMember |  |  |  |  |  |  |  |  |  |  |  |
Subsequent Event [Member] | Bank of Nova Scotia [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Borrowing capacity |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 575,000,000.0 us-gaap_LineOfCreditFacilityCurrentBorrowingCapacity / us-gaap_LineOfCreditFacilityAxis = gpor_BankofNovaScotiaMember / us-gaap_SubsequentEventTypeAxis = us-gaap_SubsequentEventMember
[1] | On October 17, 2012, the Company issued $250.0 million in aggregate principal amount of October Notes to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act, (the "October Notes Offering") under an indenture among the Company, its subsidiary guarantors and Wells Fargo Bank, National Association, as the trustee, (the "senior note indenture"). On December 21, 2012, the Company issued an additional $50.0 million in aggregate principal amount of December Notes to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the December Notes Offering"). The December Notes were issued as additional securities under the senior note indenture. The October Notes Offering and the December Notes Offering are collectively referred to as the "Notes Offerings". The Company used a portion of the net proceeds from the October Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of October Notes Offering and the net proceeds of the December Notes Offering for general corporate purposes, which included funding a portion of its 2013 capital development plan. The October Notes and the December Notes were exchanged for substantially identical notes in the same aggregate principal amount that were registered under the Securities Act in October 2013 (the "Exchange Notes").On August 18, 2014, the Company issued an additional $300.0 million in aggregate principal amount of senior unsecured notes due 2020 (the "August Notes") to qualified institutional buyers pursuant to Rule 144A under the Securities Act and to certain non-U.S. persons in accordance with Regulation S under the Securities Act ("the August Notes Offering"). The August Notes were issued as additional securities under the senior note indenture. The Company used a portion of the net proceeds from the August Notes Offering to repay all amounts outstanding at such time under its revolving credit facility. The Company used the remaining net proceeds of the August Notes Offering for general corporate purposes, including funding a portion of its 2014 capital development plans. The October Notes Offering, December Notes Offering and the August Notes Offering are collectively referred to as the "Notes Offerings" and the Exchange Notes, and the August Notes are collectively referred to as the "Notes".In connection with the issuance of the August Notes, the Company and the subsidiary guarantors entered into a registration rights agreement with the initial purchasers on August 18, 2014, pursuant to which the Company and the subsidiary guarantors have agreed to file a registration statement with respect to an offer to exchange the August Notes for a new issue of substantially identical debt securities registered under the Securities Act. The registration statement relating to the exchange offer for the August Notes was filed on November 6, 2014, as amended on February 3, 2015, and declared effective by the SEC on February 4, 2015. The exchange offer for the August Note is expected to be completed on or about March 10, 2015.Under the senior note indenture, interest on the Notes accrues at a rate of 7.75% per annum on the outstanding principal amount from October 17, 2012, payable semi-annually on May 1 and November 1 of each year, commencing on May 1, 2013. The Notes are the Company's senior unsecured obligations and rank equally in the right of payment with all of the Company's other senior indebtedness and senior in right of payment to any future subordinated indebtedness. All of the Company's existing and future restricted subsidiaries that guarantee the Company's secured revolving credit facility or certain other debt guarantee the Notes; provided, however, that the Notes are not guaranteed by Grizzly Holdings, Inc. and will not be guaranteed by any of the Company's future unrestricted subsidiaries. The Company may redeem some or all of the Notes at any time on or after November 1, 2016, at the redemption prices listed in the senior note indenture. Prior to November 1, 2016, the Company may redeem the Notes at a price equal to 100% of the principal amount plus a “make-whole” premium. In addition, prior to November 1, 2015, the Company may redeem up to 35% of the aggregate principal amount of the Notes with the net proceeds of certain equity offerings, provided that at least 65% of the aggregate principal amount of the Notes initially issued remains outstanding immediately after such redemption.
[2] | In March 2011, the Company entered into a new building loan agreement for the office building it occupies in Oklahoma City, Oklahoma. The new loan agreement refinanced the $2.4 million outstanding under the previous building loan agreement. The new agreement matures in February 2016 and bears interest at the rate of 5.82% per annum. The new building loan requires monthly interest and principal payments of approximately $22,000 and is collateralized by the Oklahoma City office building and associated land.

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