Note 10 - Subsequent Events (Details Textual)			3 Months Ended
	Jun. 25, 2020 USD ($) $ / shares	May 04, 2020 USD ($)	Jul. 02, 2020	Mar. 31, 2020 USD ($)
Line of Credit [Member] | First Lien Credit Facility [Member]
Line of Credit Facility, Current Borrowing Capacity				$ 135,000,000
Subsequent Event [Member]
Proceeds From Paycheck Protection Program Under CARES Act		$ 1,400,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member]
Working Capital Reserve	$ 3,000,000
Debt Instrument, Covenant, Maximum Capital Expenditures	$ 3,000,000
Debt Instrument, Covenant, Minimum Asset Coverage Ratio for Capital Expenditures	1.6
Debt Instrument, Covenant, Maximum Line of Credit Outstanding for Capital Expenditures	$ 50,000,000
Debt Instrument, Covenant, Maximum Outstanding and Undisputed Accounts Payable	7,500,000
Debt Instrument, Covenant, Maximum Undisputed Accounts Payable Outstanding with 60 to 90 Days	2,000,000
Debt Instrument, Covenant, Maximum Undisputed Accounts Payable Outstanding with Over 90 Days	1,000,000
Debt Instrument, Covenant, Maximum Legal and Professional Fees Excluded from General and Administrative Expense Limitations	1,000,000
Debt Instrument, Covenant, Maximum Additional Subordinated Debt Allowed to Finance Capital Expenditures	25,000,000
Line of Credit Facility, Current Borrowing Capacity	102,000,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member] | General and Administrative Expenses for Quarter Ending June 30, 2020 [Member]
Debt Instrument, Covenant, Maximum Quarterly General and Administrative Expenses	9,000,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member] | General and Administrative Expenses for Quarter Ending September 30, 2020 [Member]
Debt Instrument, Covenant, Maximum Quarterly General and Administrative Expenses	8,250,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member] | General and Administrative Expenses for Quarter Ending December 31, 2020 [Member]
Debt Instrument, Covenant, Maximum Quarterly General and Administrative Expenses	6,900,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member] | General and Administrative Expenses for Year End December 31, 2021 [Member]
Debt Instrument, Covenant, Maximum Yearly General and Administrative Expenses	6,500,000
Subsequent Event [Member] | Line of Credit [Member] | First Lien Credit Facility [Member] | General and Administrative Expenses After Year End December 31, 2021 [Member]
Debt Instrument, Covenant, Maximum Yearly General and Administrative Expenses	5,000,000
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member]
Debt Instrument, Covenant, Maximum Outstanding and Undisputed Accounts Payable	7,500,000
Debt Instrument, Covenant, Maximum Undisputed Accounts Payable Outstanding with 60 to 90 Days	2,000,000
Debt Instrument, Covenant, Maximum Undisputed Accounts Payable Outstanding with Over 90 Days	1,000,000
Debt Instrument, Fee Amount	$ 10,000,000
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member] | Warrants Issued in Connection with Second Lien Credit Facility [Member]
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share) | $ / shares	$ 0.01
Warrants Grant Amount as a Percentage of Fully Diluted Common Equity	19.90%
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member] | General and Administrative Expenses for Quarter Ending June 30, 2020 [Member]
Debt Instrument, Covenant, Maximum Quarterly General and Administrative Expenses	$ 9,000,000
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member] | General and Administrative Expenses for Quarter Ending September 30, 2020 [Member]
Debt Instrument, Covenant, Maximum Quarterly General and Administrative Expenses	8,250,000
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member] | General and Administrative Expenses for Year End December 31, 2021 [Member]
Debt Instrument, Covenant, Maximum Yearly General and Administrative Expenses	6,500,000
Subsequent Event [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member] | General and Administrative Expenses After Year End December 31, 2021 [Member]
Debt Instrument, Covenant, Maximum Yearly General and Administrative Expenses	$ 5,000,000
Subsequent Event [Member] | Minimum [Member]
Percentage of Officers' Compensation, Decreased During Period			20.00%
Percentage of Other Salaries, Decreased During Period			5.00%
Subsequent Event [Member] | Maximum [Member]
Percentage of Officers' Compensation, Decreased During Period			40.00%
Percentage of Other Salaries, Decreased During Period			20.00%
Subsequent Event [Member] | Maximum [Member] | Line of Credit [Member] | First Lien Credit Facility [Member]
Total Debt to EBITDAX Ratio	2.75
Asset Coverage Ratio, Current	1.15
Asset Coverage Ratio, Noncurrent	1.25
Subsequent Event [Member] | Maximum [Member] | Line of Credit [Member] | Second Lien Credit Facility [Member]
Asset Coverage Ratio, Noncurrent, Year Two	1.45
Asset Coverage Ratio, Noncurrent, after Year Two	1.55