Represents the fixed charge coverage ratio.

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The maximum total debt to EBITDAX ratio required by the debt agreement.

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Represents the debt instrument libor floor.

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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Nominal or face amount used to calculate payments on the derivative liability.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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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.

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of long-term debt payable, sinking fund requirement, and other securities issued that are redeemable by holder at fixed or determinable price and date, maturing in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Note 6 - Long-term Debt (Details Textual) $ in Thousands	12 Months Ended
Note 6 - Long-term Debt (Details Textual) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Feb. 08, 2021 USD ($)	May 02, 2018 USD ($)
Long-Term Debt, Maturity, Year One	$ 15,286
Long-Term Debt, Maturity, Year Four	12,286
Long-Term Debt, Maturity, Year Five	9,286
Long-Term Debt, Maturity, Year Two	15,286
Long-Term Debt, Maturity, Year Three	32,875
Interest Rate Swap [Member]
Derivative Liability, Notional Amount	9,800
Interest Rate Swap [Member] \| Interest Expense [Member]
Gain (Loss) on Derivative Instruments, Net, Pretax, Total	$ (300)	$ (200)
Credit Agreement [Member]
Fixed Charge Coverage Ratio	1.25
Debt Instrument, Covenant, Maximum Total Debt to EBITDAX Ratio	5.0
Credit Agreement [Member] \| Subsequent Event [Member]
Fixed Charge Coverage Ratio			1.25
Debt Instrument, Covenant, Maximum Total Debt to EBITDAX Ratio			5.0
Credit Agreement [Member] \| Term Loan 2 [Member]
Debt Instrument, Interest Rate, Effective Percentage	1.00%
Long-Term Debt, Maturity, Year One	$ 9,300
Long-Term Debt, Maturity, Year Four	9,300
Long-Term Debt, Maturity, Year Five	3,100
Long-Term Debt, Maturity, Year Two	9,300
Long-Term Debt, Maturity, Year Three	$ 9,300
Credit Agreement [Member] \| Term Loan 2 [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.85%
Credit Agreement [Member] \| Term Loan 2 [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.65%
Credit Agreement [Member] \| Term Loan [Member]
Debt Instrument, Interest Rate, Effective Percentage	0.83%
Long-Term Debt, Maturity, Year One	$ 6,000
Long-Term Debt, Maturity, Year Four	3,000
Long-Term Debt, Maturity, Year Two	6,000
Long-Term Debt, Maturity, Year Three	$ 6,000
Credit Agreement [Member] \| Term Loan [Member] \| Minimum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	0.68%
Credit Agreement [Member] \| Term Loan [Member] \| Maximum [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Revolving Credit Facility [Member] \| Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Subsequent Event [Member]
Debt Instrument, LIBOR Floor			0.25%
Revolving Credit Facility [Member] \| BB&T [Member] \| Credit Agreement [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 75,000			$ 75,000
Revolving Credit Facility [Member] \| BB&T [Member] \| Credit Agreement [Member] \| Subsequent Event [Member]
Line of Credit Facility, Maximum Borrowing Capacity			$ 125,000
Revolving Credit Facility [Member] \| BB&T [Member] \| Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Subsequent Event [Member]
Debt Instrument, LIBOR Floor			0.25%
Revolving Credit Facility [Member] \| Fifth Third Bank [Member] \| Credit Agreement [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, LIBOR Floor	0.00%
Letter of Credit [Member] \| Credit Agreement [Member]
Letters of Credit Outstanding, Amount	$ 25,700