Note 4 - Long-term Debt (Details Textual) $ / shares in Units, $ in Thousands | Jul. 19, 2021USD ($) | Apr. 20, 2021USD ($)$ / sharesshares | Aug. 16, 2018USD ($) | Jun. 30, 2021USD ($) | Jun. 30, 2021USD ($) | Jun. 30, 2020USD ($) | Dec. 31, 2020USD ($) |
Long-term Debt, Total | | | | | $ 133,837 | $ 133,837 | | $ 143,731 |
Stock Issued During Period, Shares, New Issues (in shares) | shares | | | 10,900,000 | | | | | |
Debt Conversion, Converted Instrument, Amount | | | | | | 11,755 | $ 0 | |
Repayments of Other Long-term Debt | [1] | | | | | 18,576 | 1,527 | |
Gain (Loss) on Extinguishment of Debt, Total | | | | | | (4,696) | $ 0 | |
Series A Preferred Stock [Member] | New Notes Trustee [Member] | | | | | | | | |
Stock Issued During Period, Shares, New Issues (in shares) | shares | | | 1 | | | | | |
Preferred Stock, Liquidation Preference Per Share (in dollars per share) | $ / shares | | | $ 1 | | | | | |
Preferred Stock, Convertible, Percentage of Debt Instrument Converted | | | 75.00% | | | | | |
Convertible Preferred Stock, Conversion Price (in dollars per share) | $ / shares | | | $ 1 | | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | | | | | | | | |
Long-term Debt, Gross | [2] | | | | 19,750 | 19,750 | | 22,500 |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | | | | | | | | |
Debt Instrument, Covenant, Minimum Excess Borrowing Availability for Five Consecutive Business Days | | | | $ 6,250 | | | | |
Debt Instrument, Covenant, Minimum Excess Borrowing Availability on Any Given Business Day | | | | 5,000 | | | | |
Line of Credit Facility, Maximum Borrowing Capacity | | | | 50,000 | | | | |
Debt Instrument, Covenant, Maximum Borrowing Base Percentage of Net Orderly Liquidation Value, Multi-client Data Library | | | | $ 28,500 | | | | |
Long-term Line of Credit, Total | | | | | 19,800 | 19,800 | | |
Line of Credit Facility, Remaining Borrowing Capacity | | | | | 6,100 | 6,100 | | |
Debt Instrument, Covenant, Minimum Fixed Cover Charge Ratio | | | | 1.1 | | | | |
Line of Credit, Current | | | | | 19,800 | 19,800 | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Subsidiary Borrowers [Member] | | | | | | | | |
Debt Instrument, Percentage of Ownership Interest in Subsidiaries Subject to First Priority Security Interest | | | | 100.00% | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | ION International Holdings L.P. [Member] | | | | | | | | |
Debt Instrument, Percentage of Ownership Interest in Subsidiaries Subject to First Priority Security Interest | | | | 65.00% | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Subsequent Event [Member] | | | | | | | | |
Repayments of Debt | | $ 400 | | | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | GX Geoscience Corporation, S. De R.L. De C.V. [Member] | | | | | | | | |
Line of Credit Facility, Maximum Borrowing Capacity | | | | | 5,000 | 5,000 | | |
Debt Instrument, Covenant, Borrowing Base, Maximum Eligible Billed Receivables | | | | $ 5,000 | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Maximum [Member] | Base Rate [Member] | | | | | | | | |
Debt Instrument, Basis Spread on Variable Rate | | | | 3.00% | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Maximum [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | | | | | | |
Debt Instrument, Basis Spread on Variable Rate | | | | 4.00% | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Minimum [Member] | Base Rate [Member] | | | | | | | | |
Debt Instrument, Basis Spread on Variable Rate | | | | 2.00% | | | | |
Line of Credit [Member] | Revolving Credit Facility [Member] | PNC Bank, National Association [Member] | Minimum [Member] | London Interbank Offered Rate (LIBOR) [Member] | | | | | | | | |
Debt Instrument, Basis Spread on Variable Rate | | | | 3.00% | | | | |
Second Lien Notes [Member] | Senior Notes [Member] | | | | | | | | |
Long-term Debt, Total | | | $ 7,100 | | 7,100 | 7,100 | | 120,600 |
Long-term Debt, Gross | | | 120,600 | | 116,193 | 116,193 | | 0 |
New Second Lien Notes [Member] | Senior Notes [Member] | | | | | | | | |
Long-term Debt, Total | | | | | 116,200 | 116,200 | | |
Long-term Debt, Gross | | | $ 116,200 | | 7,097 | 7,097 | | $ 120,569 |
Debt Instrument, Interest Rate, Stated Percentage | | | 8.00% | | | | | |
Debt Instrument, Convertible, Number of Shares to be Issued Per $1000 (in shares) | shares | | | 333 | | | | | |
Debt Instrument, Convertible, Conversion Price (in dollars per share) | $ / shares | | | $ 3 | | | | | |
Debt Instrument, Convertible, Number of Equity Instruments | | | 38,700,000 | | | | | |
Debt Instrument, Convertible, Number of Additional Equity Instruments (in shares) | shares | | | 6,500,000 | | | | | |
Debt Instrument, Convertible, Optional Conversion Period After Issue Date (Month) | | | 18 months | | | | | |
Debt Instrument, Convertible, Threshold Trading Days | | | 20 | | | | | |
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger | | | 175.00% | | | | | |
Debt Instrument, Covenant, Sale of Certain Assets, Percentage of Proceeds to Repurchase Debt | | | 100.00% | | | | | |
New Second Lien Notes [Member] | Senior Notes [Member] | Debt Instrument, Redemption, Period One [Member] | | | | | | | | |
Debt Instrument, Redemption Price, Percentage | | | 100.00% | | | | | |
New Second Lien Notes [Member] | Senior Notes [Member] | Debt Instrument, Redemption, Period Two [Member] | | | | | | | | |
Debt Instrument, Redemption Price, Percentage | | | 100.00% | | | | | |
New Second Lien Notes [Member] | Senior Notes [Member] | Debt Instrument, Redemption, Period Three [Member] | | | | | | | | |
Debt Instrument, Redemption Price, Percentage | | | 101.00% | | | | | |
Old Notes [Member] | | | | | | | | |
Repayments of Other Long-term Debt | | | $ 17,100 | | | | | |
Exchange Offer [Member] | | | | | | | | |
Debt Conversion, Original Debt, Amount | | | 113,500 | | | | | |
Debt Conversion, Converted Instrument, Amount | | | 84,700 | | | | | |
Extinguishment of Debt, Early Tender Payment | | | $ 4,000 | | | | | |
Debt Conversion, Converted Instrument, Shares Issued (in shares) | shares | | | 6,100,000 | | | | | |
Write off of Deferred Debt Issuance Cost | | | $ 700 | | | | | |
Exchange Offer [Member] | Other Income [Member] | | | | | | | | |
Gain (Loss) on Extinguishment of Debt, Total | | | (4,700) | | $ (4,700) | $ (4,700) | | |
Debt Conversion Into Cash and Common Stock [Member] | | | | | | | | |
Debt Conversion, Converted Instrument, Amount | | | $ 15,700 | | | | | |
Exchange Offer, Early Participation [Member] | | | | | | | | |
Debt Conversion, Converted Instrument, Shares Issued (in shares) | shares | | | 1,500,000 | | | | | |
| |
[1] | Consists primarily of $17.1 million payment for the Old Notes resulting from the Exchange Offer. | |
[2] | The maturity of the revolving credit facility will accelerate if the Company is unable to repay or extend the maturity of the Existing Second Lien Notes (see detailed discussion below in "Revolving Credit Facility"). | |