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Pay vs Performance Disclosure - USD ($) | 2 Months Ended | 5 Months Ended | 6 Months Ended | 12 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | ---
Dec. 31, 2022 | May 16, 2022 | Nov. 10, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Jul. 17, 2023 | Dec. 21, 2022 | Dec. 31, 2020
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Pay vs Performance [Table Text Block] |  |  |  |
| For PEO and Interim PEO Taylor | For Interim PEO Chisholm |  |  |  |
Year | Summary Compensation Table Total for Taylor (1) (2) (3) | Compensation Actually Paid to Taylor | Summary Compensation Table Total for Chisholm (4) (5) | Compensation Actually Paid to Chisholm | Average Summary Compensation Table Total for non-PEO NEOs (6) | Average Compensation Actually Paid to non-PEO NEOs | Value of initial fixed $100 investment based on TRS | Net Income (Loss) (in thousands)
2022 | $949,997 | $1,452,146 | $ | 429,129 |  | $ | 429,129 |  | $569,665 | $621,088 | $ | 120.89 |  | $ | (569) |
2021 | 1,749,279 |  | 2,259,464 |  | — |  | — |  | 478,742 |  | 377,955 |  | 110.44 |  | (9,183) |
Named Executive Officers, Footnote [Text Block] |  |  |  | Stephen C. Taylor served as President and Chief Executive Officer (“PEO”) during all of 2021 and for 137 days until May 17, 2022 and 50 days as Interim PEO from November 11, 2022. For 2022, Mr. Taylor’s $612,000 salary and $612,000 IBP award and $612,000 LTIP award included in non-equity incentive plan compensation presented in the accompanying Summary Compensation Table has been pro-rated based on the 187 days he served as PEO. Mr. Taylor served 178 days as an employee during 2022.During 2022, John W. Chisholm served 178 days as Interim PEO from May 17, 2022 until November 11, 2022. Pursuant to a Letter Agreement, dated June 9, 2022, the Company has agreed (i) to pay Mr. Chisholm a cash payment of $100,000 compensation in connection with the execution of the agreement, (ii) to pay cash compensation of $50,000 per month during the term of the agreement, but for not less than a minimum of twelve months, (iii) to reimburse legal fees Mr. Chisholm incurred in connection with the negotiation and review of the agreement, not to exceed $5,000, and (iv) grant Mr. Chisholm a stock option award of 175,000 shares of common stock (of which 25,000 shares at a grant price of $15.00 per share were immediately vested at a fair value of $11.46 per share) pursuant to the Company’s 1998 Stock Option Plan.During 2022 and 2021, the non-PEO NEO’s are Micah C. Foster, Vice President and Chief Financial Officer and James R. Hazlett, Chief Technical Officer. |  |  |  |
PEO Total Compensation Amount |  |  |  | $ 569,665 | $ 478,742 |  |  |
PEO Actually Paid Compensation Amount |  |  |  | $ 621,088 | 377,955 |  |  |
Adjustment To PEO Compensation, Footnote [Text Block] |  |  |  | The following supplementary tables presents the adjustments necessary to determine the compensation actually paid to the named PEO and Interim PEO’s and Non-PEO NEO’s:
Adjustments to Determine Compensation "Actually Paid" for PEO/Interim PEO Taylor | 2022 | 2021
Total amount per Summary Compensation Table | $ | 949,997 |  | $ | 1,749,279 |
Adjustments to determine compensation actually paid: | — |  | — |
Deduct amount reported under Stock Awards column for Taylor | (313,545) |  | (722,160) |
Deduct amount reported under Option Awards column for Taylor | — |  | — |
Increase for Fair Value of Awards Granted during the year that remain unvested at year end | 697,215 |  | 1,143,450 |
Increase/decrease for change in Fair Value from Prior Year-end to Current Year-end of Awards Granted Prior to year that were Outstanding and Unvested as of Year-end | 103,144 |  | 105,580 |
Increase for Fair Value of Awards Granted during year that Vest during year | — |  | — |
Increase (deduction) for Change in Fair Value from Prior Year-end to Vesting Date of Awards Granted Prior to year that Vested during year | 15,335 |  | (16,684) |
Increase based on Dividends or Other Earnings Paid during year prior to Vesting Date of Award. | — |  | — |
Deduct Fair Value of Awards Granted Prior to year that were Forfeited during year | — |  | — |
Total adjustments | 502,149 |  | 510,185 |
Compensation Actual Paid to PEO/Interim PEO Taylor | $ | 1,452,146 |  | $ | 2,259,464 |
Adjustments to Determine Compensation "Actually Paid" for Interim PEO Chisholm | 2022 | 2021
Total amount per Summary Compensation Table | $ | 429,129 |  | $ | — |
Adjustments to determine compensation actually paid: |  |
Deduct amount reported under Stock Awards column for Chisholm | — |  | — |
Deduct amount reported under Option Awards column for Chisholm | (59,635) |  | — |
Increase for Fair Value of Awards Granted during the year that remain unvested at year end | — |  | — |
Increase/decrease for change in Fair Value from Prior Year-end to Current Year-end of Awards Granted Prior to year that were Outstanding and Unvested as of Year-end | — |  | — |
Increase for Fair Value of Awards Granted during year that Vest during year | 59,635 |  | — |
Increase (deduction) for Change in Fair Value from Prior Year-end to Vesting Date of Awards Granted Prior to year that Vested during year | — |  | — |
Increase based on Dividends or Other Earnings Paid during year prior to Vesting Date of Award. | — |  | — |
Deduct Fair Value of Awards Granted Prior to year that were Forfeited during year | — |  | — |
Total adjustments | — |  | — |
Compensation Actual Paid to Interim PEO Chisholm | $ | 429,129 |  | $ | — |
Non-PEO NEO Average Total Compensation Amount |  |  |  | $ 569,665 | 478,742 |  |  |
Non-PEO NEO Average Compensation Actually Paid Amount |  |  |  | $ 621,088 | 377,955 |  |  |
Adjustment to Non-PEO NEO Compensation Footnote [Text Block] |  |  |  |
Adjustments to Determine Average Compensation "Actually Paid" for Non-PEO NEOs Hazlett and Foster | 2022 | 2021
Total average amount per Summary Compensation Table for Hazlett and Foster | $ | 569,665 |  | $ | 478,742 |
Adjustments to determine average compensation actually paid: | — |  | — |
Deduct average amount reported under Stock Awards column for Hazlett and Foster | (144,908) |  | (190,163) |
Deduct average amount reported under Option Awards column for Hazlett and Foster | — |  | — |
Increase for Fair Value of Awards Granted during the year that remain unvested at year end | 183,589 |  | 130,875 |
Increase/decrease for change in Fair Value from Prior Year-end to Current Year-end of Awards Granted Prior to year that were Outstanding and Unvested as of Year-end | 9,900 |  | 6,600 |
Increase for Fair Value of Awards Granted during year that Vest during year | — |  | — |
Increase (deduction) for Change in Fair Value from Prior Year-end to Vesting Date of Awards Granted Prior to year that Vested during year | 2,842 |  | (700) |
Increase based on Dividends or Other Earnings Paid during year prior to Vesting Date of Award. | — |  | — |
Deduct Fair Value of Awards Granted Prior to year that were Forfeited during year | — |  | (47,400) |
Total adjustments | 51,423 |  | (100,787) |
Average Compensation Actual Paid to Non-PEO NEOs Hazlett and Foster | $ | 621,088 |  | $ | 377,955 |
Total Shareholder Return Amount |  |  |  | $ 120.89 | 110.44 |  |  |
Net Income (Loss) |  |  |  | $ (569,000) | $ (9,183,000) |  |  |
Additional 402(v) Disclosure [Text Block] |  |  |  | The Company has agreed that unless Mr. Taylor’s employment with the Company is terminated for Cause it will: (i) pay Mr. Taylor a salary of $51,000 per month, (ii) award Mr. Taylor $612,000 pursuant to the 2022 Annual Incentive Bonus Plan (“IBP”) of the Company as and when payments are generally made by the Company pursuant to such plan, and (iii) grant to Mr. Taylor an equity award (or cash in lieu of equity if there are not sufficient shares available) with a value of $612,000 pursuant to the 2022 LTIP of the Company as and when awards are generally made by the Company pursuant to such plan.In accordance with a Retirement Agreement, dated May 17, 2022, unless terminated by the Company for Cause prior to June 30, 2023: (i) all equity awards (and all cash awards in lieu of equity) to Mr. Taylor by the Company which have not previously vested will immediately vest, (ii) Mr. Taylor will be entitled to receive from the Company on July 17, 2023 a cash payment of $1,224,000, (iii) Mr. Taylor will be entitled to receive from the Company on July 17, 2023 a cash payment in the amount of $1,530,000 in lieu of participation in the 2023 Annual Incentive Bonus Plan of the Company, and (iv) a grant of shares of common stock of the Company on July 17, 2023 with a value of $100,000. On November 11, 2022, Mr. Chisholm’s employment agreement as Interim President and Chief Executive officer was terminated by the Company and, on December 21, 2022, Mr. Chisholm resigned from the Company’s Board of Directors pursuant to a Severance Agreement whereby stock option awards covering 150,000 shares of common stock of the previously granted stock option award of 175,000 shares were cancelled. Shareholder Return (“TSR”) for the years ended December 31, 2022 and 2021 is as follows:
TSR - (P1-P0) + D | 2022 | 2021
P1 - Ending NGS stock price - December 31, |  | $ | 11.46 |  | $ | 10.47 |
P0 = Initial stock price - December 31, 2020 |  | $ | 9.48 |  | $ | 9.48 |
D = Dividends |  | $ | — |  | $ | — |
| TSR = | 1.98 |  | 0.99 |
TSR/P0 | TSR % | 20.89 | % | 10.44 | %
TSR based on $100 investment |  | $ | 120.89 |  | $ | 110.44 |
Stock Price | $ 11.46 |  |  | $ 11.46 | $ 10.47 |  |  | $ 9.48
Dividends Paid | $ 0 |  |  | $ 0 | $ 0 |  |  |
Total Shareholder Return | $ 1.98 |  |  | $ 1.98 | $ 0.99 |  |  |
Total Shareholder Return Percentage | 20.89% |  |  | 20.89% | 10.44% |  |  |
Taylor [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
PEO Total Compensation Amount |  |  |  | $ 949,997 | $ 1,749,279 |  |  |
PEO Actually Paid Compensation Amount |  |  |  | $ 1,452,146 | $ 2,259,464 |  |  |
PEO Name |  |  |  |  | Stephen C. Taylor |  |  |
PEO, Number Of Days Served | 50 days | 137 days |  | 187 days |  |  |  |
PEO, Annual Salary |  |  |  | $ 612,000 |  |  |  |
PEO Compensation, Bonus Plan |  |  |  | 612,000 |  |  |  |
PEO Compensation, Share-Based Plan |  |  |  | $ 612,000 |  |  |  |
Number Of Days Served As Employee |  |  |  | 178 days |  |  |  |
PEO Compensation, Monthly Salary |  |  |  | $ 51,000 |  |  |  |
PEO Compensation, Retirement Agreement, Cash Payment |  |  |  |  |  | $ 1,224,000 |  |
PEO Compensation, Retirement Agreement, Cash Payment In Lieu Of Annual Incentive Bonus Plan Participation |  |  |  |  |  | 1,530,000 |  |
PEO Compensation, Retirement Agreement, Value Of Share Grant |  |  |  |  |  | $ 100,000 |  |
Chisholm [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
PEO Total Compensation Amount |  |  |  | 429,129 | $ 0 |  |  |
PEO Actually Paid Compensation Amount |  |  |  | $ 429,129 | 0 |  |  |
PEO Name |  |  |  | John W. Chisholm |  |  |  |
PEO, Number Of Days Served |  |  | 178 days |  |  |  |  |
PEO Compensation, Monthly Salary |  |  |  | $ 50,000 |  |  |  |
PEO Compensation Agreement, Cash Payment |  |  |  | 100,000 |  |  |  |
PEO Compensation Agreement, Reimbursement Of Legal Fees, Maximum |  |  |  | $ 5,000 |  |  |  |
PEO Compensation Agreement, Share-Based Payment Arrangement, Number Of Shares Granted |  |  |  | 175,000 |  |  |  |
PEO Compensation Agreement, Share-Based Payment Arrangement, Number Of Shares Granted And Vested |  |  |  | 25,000 |  |  |  |
PEO Compensation Agreement, Share-Based Payment Arrangement, Grant Price Per Share |  |  |  | $ 15.00 |  |  |  |
PEO Compensation Agreement, Share-Based Payment Arrangement, Shares Vested, Fair Value Per Share |  |  |  | $ 11.46 |  |  |  |
PEO Severance Agreement, Share-Based Payment Arrangement, Number Of Shares Cancelled |  |  |  |  |  |  | 150,000 |
PEO [Member] | Taylor [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | $ 502,149 | 510,185 |  |  |
PEO [Member] | Taylor [Member] | Stock Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | (313,545) | (722,160) |  |  |
PEO [Member] | Taylor [Member] | Option Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Taylor [Member] | Equity Awards Granted During The Year, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 697,215 | 1,143,450 |  |  |
PEO [Member] | Taylor [Member] | Equity Awards Granted In Priory Years, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 103,144 | 105,580 |  |  |
PEO [Member] | Taylor [Member] | Equity Awards Granted During The Year, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Taylor [Member] | Equity Awards Granted In Prior Years, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 15,335 | (16,684) |  |  |
PEO [Member] | Taylor [Member] | Equity Awards, Value Of Dividends And Other Earnings [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Taylor [Member] | Equity Awards Granted In Prior Years, Forfeited [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Stock Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Option Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | (59,635) | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards Granted During The Year, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards Granted In Priory Years, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards Granted During The Year, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 59,635 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards Granted In Prior Years, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards, Value Of Dividends And Other Earnings [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
PEO [Member] | Chisholm [Member] | Equity Awards Granted In Prior Years, Forfeited [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
Non-PEO NEO [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 51,423 | (100,787) |  |  |
Non-PEO NEO [Member] | Stock Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | (144,908) | (190,163) |  |  |
Non-PEO NEO [Member] | Option Awards Adjustment [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
Non-PEO NEO [Member] | Equity Awards Granted During The Year, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 183,589 | 130,875 |  |  |
Non-PEO NEO [Member] | Equity Awards Granted In Priory Years, Unvested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 9,900 | 6,600 |  |  |
Non-PEO NEO [Member] | Equity Awards Granted During The Year, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
Non-PEO NEO [Member] | Equity Awards Granted In Prior Years, Vested [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 2,842 | (700) |  |  |
Non-PEO NEO [Member] | Equity Awards, Value Of Dividends And Other Earnings [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | 0 | 0 |  |  |
Non-PEO NEO [Member] | Equity Awards Granted In Prior Years, Forfeited [Member] |  |  |  |  |  |  |  |
Pay vs Performance Disclosure [Table] |  |  |  |  |  |  |  |
Adjustment to Compensation Amount |  |  |  | $ 0 | $ (47,400) |  |  |

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