Natural Gas Services (NGS) 10-K 18 Mar 22 2021 FY Annual report Financial data

Cover

Cover - USD ($)	12 Months Ended
	Dec. 31, 2021	Mar. 14, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	1-31398
Entity Registrant Name	NATURAL GAS SERVICES GROUP, INC.
Entity Incorporation, State or Country Code	CO
Entity Tax Identification Number	75-2811855
Entity Address, Address Line One	404 Veterans Airpark Lane, Suite 300
Entity Address, City or Town	Midland
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	79705
City Area Code	(432)
Local Phone Number	262-2700
Title of 12(b) Security	Common Stock, $.01 par value
Trading Symbol	NGS
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Public Float			$ 129,415,763
Entity Common Stock, Shares Outstanding		12,717,486
Documents Incorporated by Reference	Documents incorporated by reference Certain information called for in Items 10, 11, 12, 13 and 14 of Part III are incorporated by reference to the registrant’s definitive proxy statement for the annual meeting of shareholders expected to be held on June 16, 2022.
Entity Central Index Key	0001084991
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false

Audit Information

Audit Information	12 Months Ended
	Dec. 31, 2021
Auditor Information [Abstract]
Auditor Name	Moss Adams, LLP
Auditor Location	Dallas, Texas
Auditor Firm ID	659

CONSOLIDATED BALANCE SHEETS

CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current Assets:
Cash and cash equivalents	$ 22,942	$ 28,925
Trade accounts receivable, net of allowance for doubtful accounts of $1,129 and $1,161, respectively	10,389	11,884
Inventory	19,329	19,926
Federal income tax receivable	11,538	11,538
Prepaid income taxes	51	66
Prepaid expenses and other	854	379
Total current assets	65,103	72,718
Long-Term Inventory, net of allowance for obsolescence of $64 and $221, respectively	1,582	1,065
Rental equipment, net of accumulated depreciation of $172,563 and $175,802, respectively	206,985	207,585
Property and equipment, net of accumulated depreciation of $15,784 and $13,916, respectively	20,828	21,749
Right of use assets - operating leases, net of accumulated amortization $555 and $356, respectively	285	483
Intangibles, net of accumulated amortization of $2,134 and $2,008, respectively	1,025	1,151
Other assets	2,698	2,050
Total assets	298,506	306,801
Current Liabilities:
Accounts payable	4,795	2,373
Accrued liabilities	14,103	6,770
Line of credit	0	417
Current operating leases	68	198
Deferred income	1,312	1,103
Total current liabilities	20,278	10,861
Deferred income tax liability	39,288	41,890
Long-term operating leases	217	285
Other long-term liabilities	2,813	2,221
Total liabilities	62,596	55,257
Commitments and contingencies
Stockholders’ Equity:
Preferred stock, 5,000 shares authorized, no shares issued or outstanding	0	0
Common stock, 30,000 shares authorized, par value $0.01; 13,394 and 13,296 shares issued, respectively	134	133
Additional paid-in capital	114,017	112,615
Retained earnings	130,103	139,286
Treasury shares, at cost, 775 shares and 38, respectively	(8,344)	(490)
Total stockholders' equity	235,910	251,544
Total liabilities and stockholders' equity	$ 298,506	$ 306,801

CONSOLIDATED BALANCE SHEETS (Pa

CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Current Assets:
Allowance for doubtful accounts	$ 1,129	$ 1,161
Noncurrent Assets:
Allowance for inventory obsolescence	64	221
Accumulated depreciation, rental equipment	172,563	175,802
Accumulated depreciation, property and equipment	15,784	13,916
Accumulated amortization, operating lease right of use assets	555	356
Accumulated amortization, intangibles	$ 2,134	$ 2,008
Stockholders’ Equity:
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0
Common stock, shares authorized (in shares)	30,000,000	30,000,000
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares issued (in shares)	13,394,000	13,296,000
Common stock, shares outstanding (in shares)	13,394,000	13,296,000
Treasury shares (in shares)	775,000	38,000

CONSOLIDATED STATEMENTS OF OPER

CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Revenue:
Revenues	$ 72,420	$ 68,055
Operating costs and expenses:
Cost of rentals, exclusive of depreciation stated separately below	36,638	28,506
Cost of sales, exclusive of depreciation stated separately below	7,829	6,211
Cost of service and maintenance, exclusive of depreciation stated separately below	898	714
Selling, general and administrative expenses	10,762	10,550
Depreciation and amortization	25,397	25,198
Inventory allowance	208	184
Retirement of rental equipment	3,096	291
Total operating costs and expenses	84,828	71,654
Operating loss	(12,408)	(3,599)
Other income (expense):
Interest expense	(65)	(14)
Other income	687	629
Total other income, net	622	615
Loss before income taxes:	(11,786)	(2,984)
(Provision for) benefit from income taxes:
Current	1	15,438
Deferred	2,602	(10,646)
Total income tax benefit	2,603	4,792
Net income (loss)	$ (9,183)	$ 1,808
Earnings (loss) per share:
Basic (in dollars per share)	$ (0.70)	$ 0.14
Diluted (in dollars per share)	$ (0.70)	$ 0.14
Weighted average shares outstanding:
Basic (in shares)	13,100	13,224
Diluted (in shares)	13,100	13,261
Rental income
Revenue:
Revenues	$ 63,624	$ 60,826
Sales
Revenue:
Revenues	6,882	5,657
Service and maintenance income
Revenue:
Revenues	$ 1,914	$ 1,572

CONSOLIDATED STATEMENTS OF STOC

CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Preferred Stock	Common Stock	Additional Paid-In Capital	Retained Earnings	Treasury Stock
Beginning balance (in shares) at Dec. 31, 2019		0	13,178			(38)
Beginning balance at Dec. 31, 2019	$ 247,693	$ 0	$ 132	$ 110,573	$ 137,478	$ (490)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation expense on common stock options	19			19
Issuance of restricted stock (in shares)			118
Compensation expense on restricted common stock	2,176		$ 1	2,175
Taxes paid related to net shares settlement of equity awards	(152)			(152)
Net loss	1,808				1,808
Ending balance (in shares) at Dec. 31, 2020		0	13,296			(38)
Ending balance at Dec. 31, 2020	251,544	$ 0	$ 133	112,615	139,286	$ (490)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Compensation expense on common stock options	1			1
Issuance of restricted stock (in shares)			98
Compensation expense on restricted common stock	1,738		$ 1	1,737
Taxes paid related to net shares settlement of equity awards	(336)			(336)
Purchase of treasury shares (in shares)						737
Purchase of treasury shares	(7,854)					$ (7,854)
Net loss	(9,183)				(9,183)
Ending balance (in shares) at Dec. 31, 2021		0	13,394			(775)
Ending balance at Dec. 31, 2021	$ 235,910	$ 0	$ 134	$ 114,017	$ 130,103	$ (8,344)

CONSOLIDATED STATEMENTS OF CASH

CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
CASH FLOWS FROM OPERATING ACTIVITIES:
Net (loss) income	$ (9,183)	$ 1,808
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Depreciation and amortization	25,397	25,198
Amortization of debt issuance costs	31	0
Deferred taxes	(2,602)	10,646
Gain on disposal of assets	(182)	(284)
Retirement of rental equipment	3,096	291
Bad debt allowance	65	329
Inventory allowance	208	184
Stock-based compensation	1,738	2,195
Gain on company owned life insurance	(298)	(168)
Changes in operating assets and liabilities:
Trade accounts receivables	1,430	(3,107)
Inventory	(1,277)	1,033
Prepaid income taxes and prepaid expenses	(460)	(11,346)
Accounts payable and accrued liabilities	9,756	4,880
Deferred income	208	463
Other	600	527
NET CASH PROVIDED BY OPERATING ACTIVITIES	28,527	32,649
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of rental equipment, property and other equipment	(25,710)	(15,257)
Purchase of company owned life insurance	(150)	(296)
Proceeds from sale of property and equipment	195	394
NET CASH USED IN INVESTING ACTIVITIES	(25,665)	(15,159)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds of other long-term liabilities	(1)	(5)
Repayments of line of credit, net	(417)	0
Payments of debt issuance costs	(237)	0
Purchase of treasury shares	(7,854)	0
Taxes paid related to net share settlement of equity awards	(336)	(152)
NET CASH USED IN FINANCING ACTIVITIES	(8,845)	(157)
NET CHANGE IN CASH AND CASH EQUIVALENTS	(5,983)	17,333
CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD	28,925	11,592
CASH AND CASH EQUIVALENTS AT END OF PERIOD	22,942	28,925
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Interest paid	30	14
Income taxes paid	0	105
NON-CASH TRANSACTIONS
Right of use asset acquired through an operating lease	$ 0	$ 77

Description of Business

Description of Business	12 Months Ended
	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Description of Business	Description of BusinessNatural Gas Services Group, Inc. (the "Company", “NGS”, "Natural Gas Services Group", "we" or "our") (a Colorado corporation), is a leading provider of natural gas compression equipment and services to the energy industry. The Company manufactures, fabricates, rents, sells and maintains natural gas compressors and flare systems for oil and natural gas production and plant facilities. NGS is headquartered in Midland, Texas, with fabrication facilities located in Tulsa, Oklahoma and Midland, Texas, and service facilities located in major oil and natural gas producing basins in the U.S. The Company was formed on December 17, 1998.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company, its subsidiary, NGSG Properties, LLC and the rabbi trust associated with the Company’s deferred compensation plan, see Note 10. All significant intercompany accounts and transactions for the periods presented have been eliminated in consolidation. Use of Estimates The preparation of our consolidated financial statements in conformity with generally accepted accounting principles in the United States of America requires our management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Significant estimates include fixed asset lives, bad debt allowance and the allowance for inventory obsolescence. Additionally, NGS conducts a yearly review of impairment of long-lived assets. Throughout the review, determining factors are based on estimates that can significantly impact the carrying value of these assets. It is at least reasonably possible these estimates could be revised in the near term and the revisions could be material. Cash Equivalents and Financial Instruments For purposes of reporting cash flows, we consider all short-term investments with an original maturity of three months or less to be cash equivalents. We invest our cash primarily in deposits and money market funds with commercial banks. At times, cash balances at banks and financial institutions may exceed federally insured amounts. We believe that the risk to our cash balance is minimal because we have chosen a large regional bank with strong long-term ratings of Baa3/BBB-. Accounts Receivable Our trade receivables consist of customer obligations for the sale of compressors and flare systems due under normal trade terms, and operating leases for the use of our natural gas compressors. The receivables are not collateralized except as provided for under lease agreements. However, we typically require deposits of as much as 50% or use of progress payments for large custom sales contracts. We perform ongoing credit evaluations of our customers and adjust credit limits based on management's assessment of the customer's financial condition and payment history, as well as industry conditions and general economic conditions. We continuously monitor collections and payments from our customers, and maintain a provision for estimated credit losses based upon our historical experience and any specific customer collection issues that we have identified. While such credit losses have historically been within our expectations and the provisions established, we cannot guarantee that we will continue to experience the same credit loss rates that we have in the past. One customer accounted for 46% and 35% of our accounts receivable as of December 31, 2021 and 2020, respectively. A significant change in the liquidity or financial position of this customer could have a material adverse impact on the collectability of our accounts receivable and our future operating results. The allowance for doubtful accounts was $1.1 million and $1.2 million at December 31, 2021 and 2020, respectively. Management believes that the allowance is adequate; however, actual write-offs may exceed the recorded allowance. A summary of our allowance for doubtful accounts is as follows: Year Ended December 31, ($ in thousands) 2021 2020 Beginning balance $ 1,161 $ 918 Accruals 65 329 Recoveries 8 — Write-offs (105) (86) Ending balance $ 1,129 $ 1,161 Revenue Recognition Policy Revenue is measured based on a consideration specified in a customer’s contract, excluding any sale incentives and taxes collected on behalf of third parties (i.e. sales and property taxes). Revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration that we expect to receive for those goods or services. To recognize revenue, we (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when, or as, we satisfy the performance obligation(s). Shipping and handling costs incurred are accounted for as fulfillment costs and are included in cost of revenues in our Consolidated Statements of Operations. Nature of Goods and Services The following is a description of principal activities from which the Company generates its revenue: Rental Revenue . The Company generates revenue from renting compressors and flare systems to our customers. These contracts, which all qualify as operating leases under ASC Topic 842, Leases (ASC 842), may also include a fee for servicing the compressor or flare during the rental contract. Our rental contracts typically range from six Sales Revenue. The Company generates revenue by the sale of custom/fabricated compressors, flare systems and parts, as well as, exchange/rebuilding customer owned compressors and sale of used rental equipment. Custom/fabricated compressors and flare systems - The Company designs and fabricates compressors and flares based on the customer’s specifications outlined in their contract. Though the equipment being built is customized by the customer, control under these contracts does not pass to the customer until the compressor or flare package is completed and shipped, or in accordance with a bill and hold arrangements the customer accepts title and assumes the risk and rewards of ownership. We request some of our customers to make progressive payments as the product is being built; these payments are recorded as a contract liability on the Deferred Income line on the consolidated balance sheet until control has been transferred. These contracts also may include an assurance warranty clause to guarantee the product is free from defects in material and workmanship for a set duration of time; this is a standard industry practice and is not considered a performance obligation. From time to time, upon the customer’s written request, we recognize revenue when manufacturing is complete and the equipment is ready for shipment. At the customer’s request, we will bill the customer upon completing all performance obligations, but before shipment. The customer will formally request we ship the equipment per their direction from our manufacturing facility at a later specified date and that we segregate the equipment from our finished goods, such that they are not available to fill other orders. Per the customer’s agreement change of control is passed to the customer once the equipment is complete and ready for shipment. We have operated using bill and hold agreements with certain customers for many years, with consistent satisfactory results for both the customer and us. The credit terms on these agreements are consistent with the credit terms on all other sales. All control is shouldered by the customer and there are no exceptions to the customer’s commitment to accept and pay for the manufactured equipment. Revenues recognized related to bill and hold arrangements for the years ended December 31, 2021 and 2020 was approximately $20,000 and $852,000, respectively. Parts - Revenue is recognized after the customer obtains control of the parts. Control is passed either by the customer taking physical possession or the parts being shipped. The amount of revenue recognized is not adjusted for expected returns, as our historical part returns have been de minimis. Exchange or rebuilding customer owned compressors - Based on the contract, the Company will either exchange a new/rebuilt compressor for the customer’s malfunctioning compressor or rebuild the customer’s compressor. Revenue is recognized after control of the replacement compressor has transferred to the customer based on the terms of the contract, i.e., by physical delivery, delivery and installment, or shipment of the compressor. Used compressors or flares - From time to time, a customer may request to purchase a used compressor or flare out of our rental fleet. Revenue from the sale of rental equipment is recognized when the control has passed to the customer based on the terms of the contract, i.e. when the customer has taken physical possession or the equipment has been shipped. Service and Maintenance Revenue. The Company provides routine or call-out services on customer owned equipment. Revenue is recognized after services in the contract are rendered. Payment terms for sales revenue and service and maintenance revenue discussed above are generally 30 to 60 days although terms for specific customers can vary. Also, the transaction prices are not subject to variable consideration constraints. Disaggregation of Revenue The following table shows the Company's revenue disaggregated by product or service type for the years ended: Year Ended December 31, 2021 2020 (in thousands) Compressors - sales $ 1,891 $ 2,211 Flares - sales 365 489 Other (Parts/Rebuilds) - sales 4,626 2,957 Service and maintenance 1,914 1,572 Total revenue from contracts with customers 8,796 7,229 Add: ASC 842 rental revenue 63,624 60,826 Total revenue $ 72,420 $ 68,055 Contract Balances As of December 31, 2021 and 2020, we had the following receivables and deferred income from contracts with customers: December 31, 2021 2020 (in thousands) Accounts Receivable Accounts receivable - contracts with customers $ 3,354 $ 3,243 Accounts receivable - ASC 842 8,164 9,802 Total Accounts Receivable 11,518 13,045 Less: Allowance for doubtful accounts (1,129) (1,161) Total Accounts Receivable, net $ 10,389 $ 11,884 Deferred income $ 1,312 $ 1,103 The Company recognized $1.1 million in revenue for the year ended December 31, 2021 that was included in deferred income at the beginning of 2021. For the period ended December 31, 2020, the Company recognized revenue of $73,000 from amounts related to sales that were included in deferred income at the beginning of 2020. The increases (decreases) of accounts receivable and deferred income were primarily due to normal timing differences between our performance and the customers’ payments. T ransaction Price Allocated to the Remaining Performance Obligations As of December 31, 2021, the Company did not have revenue related to unsatisfied performance obligations. Contract Costs The Company recognizes the incremental costs of obtaining contracts as an expense when incurred if the amortization period of the assets that the Company otherwise would have recognized is one year or less. These costs are included in selling, general and administrative expense on our Consolidated Statements of Operations. Leases Accounting Standards Codification ("ASC") 842 requires all leases to be reported on the balance sheet as right-of-use ("ROU") assets and lease obligations. We determine if an arrangement is a lease at inception and determine lease classification and recognize ROU assets and liabilities on the lease commencement date based on the present value of lease payments over the lease term. As the discount rate implicit in the lease is rarely readily determinable, we estimate our incremental borrowing rate using information available at the commencement date in determining the present value of the lease payments. We, as a lessee, apply the practical expedient to not separate non-lease components from lease components, therefore, accounting for each separate lease component and its associated non-lease component, as a single lease component. For each lease that 1) contains the same timing and pattern of transfer for lease and non-lease components and 2) if the lease component, if accounted for separately, would be classified as an operating lease, the Company has elected to not separate non-lease components from lease components. Major Customers and Concentration of Credit Risk Sales and rental income from Occidental Permian, LTD. ("Oxy") in 2021 and 2020 amounted to 40% and 30% of revenue, respectively. No other single customer accounted for more than 10% of our revenues in 2021 and 2020. Oxy's accounts receivable balances amounted to 46% and 35% of our accounts receivable as of December 31, 2021 and 2020, respectively. No other customers amounted to more than 10% of our accounts receivable as of December 31, 2021 and 2020. Inventory Inventory (current and long-term) is valued at the lower of cost and net realizable value. The cost of inventories is determined by the weighted average method. We regularly review inventory quantities on hand and record a provision for excess and obsolete inventory based primarily on current and anticipated customer demand and production requirements. The Company assesses anticipated customer demand based on current and upcoming capital expenditure budgets of its major customers as well as other significant companies in the industry, along with oil and natural gas price forecasts and other factors affecting the industry. In addition, our long-term inventory consists of raw materials and replacement parts that remain viable but which the Company does not expect to sell within the next year. Rental Equipment and Property and Equipment Rental equipment and property and equipment are recorded at cost less accumulated depreciation, except for work-in-progress on new rental equipment which is recorded at cost until it’s complete and added to the fleet. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Our rental equipment has an estimated useful life between 15 and 25 years, while our property and equipment has an estimate useful lives which range from 3 to 39 years. The majority of our property and equipment, including rental equipment, is a direct cost to generating revenue. We assess the impairment of rental equipment and property and equipment whenever events or changes in circumstances indicate that the net recorded amount may not be recoverable. The following factors could trigger an impairment review: significant underperformance relative to historical or projected future cash flows; significant adverse changes in the extent or manner in which asset (or asset group) is being used or its condition, including a meaningful drop in fleet utilization over the prior four quarters; significant negative industry or company-specific trends or actions, including meaningful capital expenditure budget reductions by our major customers or other sizable exploration and production or midstream companies, as well as significant declines in oil and natural gas prices; legislative changes prohibiting us from leasing our units or flares; or poor general economic conditions. An impairment loss is recognized if the future undiscounted cash flows associated with the asset (or asset group) and the estimated fair value of the asset are less than the asset's carrying value. Sales of equipment out of the rental fleet are included with sales revenue and cost of sales, while retirements of units are shown a separate operating expense. Gains and losses resulting from sales and dispositions of other property and equipment are included with other income. Maintenance and repairs are charged to cost of rentals as incurred. Intangibles At December 31, 2021 and 2020, NGS had intangible assets, which relate to developed technology and a trade name. Developed technology is amortized on a straight-line basis with a useful life of 20 years, with a weighted average remaining life of approximately four years as of December 31, 2021. NGS has an intangible asset related to the trade name of SCS which was acquired in our acquisition of Screw Compression Systems in January 2005. This asset is not being amortized as it has been deemed to have an indefinite life. Our policy is to review intangibles that are being amortized for impairment when indicators of impairment are present. In addition, it is our policy to review indefinite-lived intangible assets for impairment annually or when indicators of impairment are present. We review intangibles through an assessment of the estimated future cash flows related to such assets. In the event that assets are found to be carried at amounts in excess of estimated undiscounted future cash flows, then the assets will be adjusted for impairment to a level commensurate with a discounted cash flow analysis of the underlying assets. Warranty When warranted, we accrue amounts for estimated warranty claims based upon current and historical product warranty costs and any other related information known. There was no warranty reserve as of December 31, 2021 and 2020. Income Taxes Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases, and operating losses and tax credit carry-forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not probable, we establish a valuation allowance. To the extent we establish a valuation allowance or increase this allowance in a period, we include an expense in the tax provision in the statement of income. ASC Topic 740 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. In order to record any financial statement benefit, we are required to determine, based on technical merits of the position, whether it is more likely than not (a likelihood of more than 50 percent) that a tax position will be sustained upon examination, including resolution of any related appeals or litigation processes. If that step is satisfied, then we must measure the tax position to determine the amount of benefit to recognize in the financial statements. The tax position is measured at the largest amount of the benefit that is greater than 50 percent likely of being realized upon ultimate settlement. Our policy regarding income tax interest and penalties is to expense those items as other expense. We account for uncertain tax positions in accordance with guidance in FASB ASC 740, which prescribes the minimum recognition threshold a tax position taken or expected to be taken in a tax return is required to meet before being recognized in the financial statements. We have no uncertain tax positions as of December 31, 2021. Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date under current market conditions. ASC Topic 820 established a fair value hierarchy, which requires an entity to maximize the use of observable inputs when measuring fair value. These inputs are categorized as follows: Level 1- quoted prices in an active market for identical assets or liabilities; Level 2- quoted prices in an active market for similar assets or liabilities, inputs other than quoted prices that are observable for similar assets or liabilities, inputs derived principally from or corroborated by observable market data by correlation or other means; and Level 3- valuation methodology with unobservable inputs that are significant to the fair value measurement. Management believes that the fair value of our cash and cash equivalents, trade receivables, accounts payable and line of credit at December 31, 2021 and 2020 approximate their carrying values due to the short-term nature of the instruments or the use of prevailing market interest rates. Segments and Related Information ASC 280-10-50, “Operating Segments”, define the characteristics of an operating segment as a) being engaged in business activity from which it may earn revenue and incur expenses, b) being reviewed by the company's chief operating decision maker (CODM) for decisions about resources to be allocated and assess its performance and c) having discrete financial information. Although we indeed look at our products to analyze the nature of our revenue, other financial information, such as certain costs and expenses, net income and EBITDA are not captured or analyzed by these categories. Our CODM does not make resource allocation decisions or access the performance of the business based on these categories, but rather in the aggregate. Based on this, management believes that it operates in one business segment. We are engaged in the business of designing and manufacturing compressors and flares. Our compressors and flares are sold and rented to our customers. In addition, we provide service and maintenance on compressors in our fleet and to third parties. These business activities are similar in all geographic areas. Our manufacturing process is essentially the same for the entire Company and is performed in house at our facilities in Midland, Texas and Tulsa, Oklahoma. Our customers primarily consist of entities in the business of producing natural gas. The maintenance and service of our products is consistent across the entire Company and is performed via an internal fleet of vehicles. The regulatory environment is similar in every jurisdiction in that the most impacting regulations and practices are the result of federal energy policy. Recently Issued Accounting Pronouncements In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform, which provides temporary optional guidance to companies impacted by the transition away from the London Interbank Offered Rate ("LIBOR"). The guidance provides certain expedients and exceptions to applying GAAP in order to lessen the potential accounting burden when contracts, hedging relationships and other transactions that reference LIBOR as a benchmark rate are modified. This guidance is effective upon issuance and expires on December 31, 2022. We are currently evaluating the impact of the LIBOR transition and this ASU 2020-04 on our consolidated financial statements.

Inventory

Inventory	12 Months Ended
	Dec. 31, 2021
Inventory Disclosure [Abstract]
Inventory	Inventory Our inventory, net of allowance for obsolescence of $64,000 and $221,000 at December 31, 2021 and 2020, respectively, consisted of the following: December 31, 2021 2020 (in thousands) Raw materials - current $ 17,528 $ 18,026 Work-in-process 1,801 1,900 Inventory - current 19,329 19,926 Raw materials - long term (net of allowances of $64 and $221, respectively) 1,582 1,065 Inventory - total $ 20,911 $ 20,991 Our long-term inventory consists of raw materials that remain viable but which the Company does not expect to sell within the next year. Inventory Allowance We routinely review our inventory allowance balance to account for slow moving or obsolete inventory costs that may not be recoverable in the future. A summary of our inventory allowance is as follows: Year Ended December 31, 2021 2020 (in thousands) Beginning balance $ 221 $ 24 Accruals 208 251 Write-offs (365) (54) Ending balance $ 64 $ 221

Rental Equipment, Property and

Rental Equipment, Property and Equipment	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Rental Equipment, Property and Equipment	Rental Equipment, Property and Equipment Rental Equipment Our rental equipment and associated accumulated depreciation as of December 31, 2021 and 2020, respectively, consisted of the following: December 31, 2021 2020 (in thousands) Compressor units $ 374,336 $ 379,623 Work-in-progress 5,212 3,764 Rental equipment 379,548 383,387 Accumulated depreciation (172,563) (175,802) Rental equipment, net of accumulated depreciation $ 206,985 $ 207,585 Our rental equipment has an estimated useful life between 15 and 25 years. Depreciation expense for rental equipment was $22.9 million and $22.7 million for the year ended December 31, 2021 and 2020, respectively. During the year ended December 31, 2021 we added 65 units to our rental fleet, 35 of which were repurchased from a significant customer who had previously purchased these units from us under a bill and hold arrangement in prior years, but had not yet placed the units in service. Retirement of Rental Equipment Company management routinely reviews its inventory of rental equipment for retirement or obsolescence. During 2021, management reviewed the rental fleet to determine which units were not of the type, configuration, make or model that our customers are demanding or that were not cost efficient to refurbish, maintain and/or operate. As a result of this review, we determined 263 units should be retired from our rental fleet. Accordingly, we recorded a $3.1 million loss on retirement of rental equipment during the year ended December 31, 2021. During our review of our rental compressor units in 2020, we determined 216 units should be retired from our rental fleet. We recorded a $0.3 million loss on retirement of rental equipment. Property and Equipment Property and equipment consists of the following at December 31, 2021 and 2020: December 31, Useful Lives (Years) 2021 2020 ($ in thousands) Land — $ 1,680 $ 1,680 Building 39 18,977 18,977 Leasehold improvements 39 1,197 1,168 Office equipment and furniture 5 2,016 2,016 Software 5 573 573 Machinery and equipment 7 3,874 3,653 Vehicles 3 8,295 7,598 Total 36,612 35,665 Less accumulated depreciation (15,784) (13,916) Total $ 20,828 $ 21,749 Depreciation expense for property and equipment was $2.4 million and $2.3 million for the year ended December 31, 2021 and 2020, respectively. Depreciation Expense by Product Line The following table depicts annual depreciation expense associated with each product line as well as our corporate activities at December 31, 2021 and 2020: December 31, 2021 2020 (in thousands) Rentals $ 24,423 $ 24,255 Sales 281 281 Service & Maintenance 49 42 Corporate 476 495 Total $ 25,229 $ 25,073

Rental Activity

Rental Activity	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Rental Activity	Rental Activity We rent natural gas compressor packages to entities in the petroleum industry. These rental arrangements are classified as operating leases and generally have original terms of six months to sixty months and continue on a month-to-month basis thereafter. Future minimum rent payments for arrangements not on a month-to-month basis at December 31, 2021 are as follows: Years Ending December 31, (in thousands) 2022 $29,583 2023 18,684 2024 18,277 2025 8,739 2026 2,614 Thereafter 462 Total $78,359

Leases

Leases	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Leases	Leases The Company determines if an arrangement is a lease at inception by assessing whether it conveys the right to control the use of an identified asset for a period of time in exchange for consideration. The Company’s leases are primarily related to property leases for its field offices. The Company's leases have remaining lease terms of one The Company's lease agreements do not contain any contingent rental payments, material residual guarantees or material restrictive covenants. Right of use assets and lease liabilities are recognized at the lease commencement date based on the present value of lease payments over the lease term. As substantially all of the Company's leases do not provide an implicit rate, the Company uses its incremental borrowing rate, which is based on a fully collateralized loan over the lease term, to determine the present value of lease payments. The Company has no finance leases. The following table reflects the amounts related to leases that are recorded on our consolidated balance sheets as of December 31, 2021 and 2020: Classification on Consolidated December 31, Balance Sheets 2021 2020 ($ in thousands) Operating lease assets Right of use assets-operating leases $ 285 $ 483 Current lease liabilities Current operating leases $ 68 $ 198 Noncurrent lease liabilities Long-term operating leases 217 285 Total lease liabilities $ 285 $ 483 Weighted average remaining lease term in years 6.6 1.5 Implicit Rate 3.4 % 3.2 % Operating lease costs are recognized on a straight-line basis over the lease term. Total operating lease costs for the year ended December 31, 2021 was approximately $556,000. December 31, 2021 2020 (in thousands) Cash paid for amounts included in the measurement of lease liabilities Operating lease cost (1) (2) $ 556 $ 550 (1) Lease costs are classified on the Consolidated Statements of Operations in cost of sales, cost of compressors and selling, general and administrative expenses. (2) Includes costs of $346,000 for leases with terms of 12 months or less and $210,000 for leases with terms greater than 12 months for the year ended December 31, 2021. Includes costs of $333,000 for leases with terms of 12 months or less and $217,000 for leases with terms greater than 12 months for the year ended December 31, 2020. The following table shows the future maturities of lease liabilities: Years Ending December 31, Lease Liabilities (in thousands) 2022 $ 77 2023 38 2024 38 2025 38 2026 38 Thereafter 92 Total lease payments 321 Less: Imputed interest (36) Total $ 285 Rent expense under such leases was $210,000 and $217,000 for the years ended December 31, 2021 and 2020, respectively.

Intangibles

Intangibles	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Intangibles	Intangibles At December 31, 2021 and 2020, the Company had intangible assets, which relate to developed technology and a trade name. Amortization expense recognized in each of the years ending December 31, 2021 and 2020 was $125,000. Estimated amortization expense for the years 2022-2024 is approximately $125,000 per year. The Company has an intangible asset with a gross carrying value of $654,000 at December 31, 2021 related to the trade name of SCS which was acquired in our acquisition of Screw Compression Systems in January 2005. This asset is not being amortized as it has been deemed to have an indefinite life. The following table represents the identified intangible assets by major asset class (in thousands): December 31, 2021 December 31, 2020 Useful Life (years) Gross Carrying Value Accumulated Amortization Net Book Value Gross Carrying Value Accumulated Amortization Net Book Value Developed Technology 20 $ 2,505 $ 2,134 $ 371 $ 2,505 $ 2,008 $ 497 Trade Name Indefinite 654 — 654 654 — 654 Total $ 3,159 $ 2,134 $ 1,025 $ 3,159 $ 2,008 $ 1,151

Credit Facility

Credit Facility	12 Months Ended
	Dec. 31, 2021
Debt Disclosure [Abstract]
Credit Facility	Credit Facility Previous Credit Agreement We had a senior secured revolving credit agreement (the "Previous Credit Agreement") with JP Morgan Chase Bank, N.A (the "Lender") that matured on March 31, 2021. Prior to maturation, the outstanding balance of $417,000 was repaid. The Previous Credit Agreement had an aggregate commitment of $30 million, subject to collateral availability. New Credit Agreement On May 11, 2021, we entered into a five year senior secured revolving credit agreement ("New Credit Agreement") with Texas Capital Bank, National Association (the "Lender") with an initial commitment of $20 million and an accordion feature that would increase the maximum commitment to $30 million, subject to collateral availability. We also have a right to request from the Lender, on an uncommitted basis, an increase of up to $30 million on the aggregate commitment; provided, however, the aggregate commitment amount is not permitted to exceed $50 million. The maturity date of the New Credit Agreement is May 11, 2026. The obligations under the New Credit Agreement are secured by a first priority lien on a variety of our assets, including inventory and accounts receivable as well as a variable number of our leased compressor equipment. Borrowing Base. At any time before the maturity of the New Credit Agreement, we may draw, repay and re-borrow amounts available under the borrowing base up to the maximum aggregate availability discussed above. Generally, the borrowing base equals the sum of (a) 90% of eligible accounts receivable owed to the Company by investment grade debtors, plus (b) 85% of the eligible accounts receivable owing by non-investment grade debtors, plus (c) 50% of the eligible inventory, valued at the lower of cost or market value at such time, subject to a cap of this component not to exceed $2 million, plus (d) the lesser of (i) 95% of the net book value of the compressors that the Lender has determined are eligible for the extension of credit, valued at the lower of cost or market value with depreciation not to exceed 25 years, at such time and (ii) 80% of the net liquidation value percentage of the net book value of the eligible compressors that the Lender has determined are eligible for the extension of credit, valued at the lower of cost or market value with depreciation not to exceed 25 years, at such time, plus (e) 80% of the value at cost (excluding any costs for capitalized interest or other non-cash capitalized costs) of the eligible new compressor fleet, minus (f) any required availability reserves determined by the Lender in its sole discretion. The Lender may adjust the borrowing base components if material deviations in the collateral are discovered in future audits of the collateral. As of December 31, 2021, our allowable borrowing base was $20.0 million. Interest and Fees. Under the terms of the New Credit Agreement, we have the option of selecting the applicable variable rate for each revolving loan, or portion thereof, of either (a) the Base Rate (as defined below) plus the Applicable Margin, or (b) in the case of a Eurodollar Rate Loan, the Adjusted Eurodollar Rate plus the Applicable Margin. "Base Rate" means, for any day, a rate of interest per annum equal to the highest of (a) the prime rate for such day; (b) the sum of the federal funds rate for such day plus 0.50%; and (c) the Adjusted Eurodollar Rate for such day plus 1.00%. The Applicable Margin is determined based upon the leverage ratio as set forth in the most recent compliance certificate received by the Lender for each fiscal quarter from time to time pursuant to the New Credit Agreement. Depending on the leverage ratio, the Applicable Margin can be 0.25% to 0.75% for Base Rate Loans (as defined in the New Credit Agreement) and 1.25% to 1.75% for Eurodollar Rate Loans and for requested letters of credit. In addition, we are required to pay a monthly commitment fee on the daily average unused amount of the commitment while the New Credit Agreement is in effect at an annual rate equal to 0.25% of the unused commitment amount. Accrued interest is payable monthly on outstanding principal amounts and unused commitment fee, provided that accrued interest on Eurodollar Rate Loans is payable at the end of each interest period, but in no event less frequently than quarterly. Covenants. The New Credit Agreement contains customary representations and warranties, as well as covenants which, among other things, condition or limit our ability to incur additional indebtedness and liens; enter into transactions with affiliates; make acquisitions in excess of certain amounts; pay dividends; redeem or repurchase capital stock or senior notes; make investments or loans; make negative pledges; consolidate, merge or effect asset sales; or change the nature of our business. In addition, we also have certain financial covenants that are applicable during certain trigger periods specified in the Credit Agreement and require us during such trigger periods to maintain a leverage ratio less than or equal to 3.00 to 1.00 as of the last day of each fiscal quarter and a fixed charge coverage ratio greater than or equal to 1.00 to 1.00 as of the last day of each fiscal quarter. Events of Default and Acceleration. The New Credit Agreement contains customary events of default for credit facilities of this size and type, and includes, without limitation, payment defaults; defaults in performance of covenants or other agreements contained in the Credit Agreement and the other transaction documents; inaccuracies in representations and warranties; certain defaults, termination events or similar events; certain defaults with respect to any other Company indebtedness in excess of $1.0 million; certain bankruptcy or insolvency events; the rendering of certain judgments in excess of $1.0 million; certain ERISA events; certain change in control events and the defectiveness of any liens under the secured revolving credit agreement. Obligations outstanding under the Credit Agreement may be accelerated upon the occurrence of an event of default.

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes The (provision for) benefit from income taxes for the years ended December 31, 2021 and 2020, consists of the following (in thousands): 2021 2020 Current benefit: Federal benefit $ — $ 15,587 State (expense) benefit 1 (149) Total current benefit 1 15,438 Deferred benefit: Federal benefit (expense) 1,991 (10,234) State benefit (expense) 611 (412) Total deferred benefit (expense) 2,602 (10,646) Total benefit $ 2,603 $ 4,792 The effective tax rate for the years ended December 31, 2021 and 2020, differs from the statutory rate as follows: 2021 2020 Statutory rate 21.0 % 21.0 % State and local taxes 5.2 % (17) % Stock based compensation (0.7) % (13.1) % Nondeductible compensation (3.6) % (11.6) % Effect of CARES Act — % 180.3 % Other 0.2 % 0.5 % Effective rate 22.1 % 160.1 % Effective rate 22.1 % 160.1 % On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act ("CARES Act") was enacted in response to the economic impact caused by the COVID-19 pandemic. The CARES Act, among other things, permits federal income tax net operating loss ("NOL") carryovers and carrybacks to offset 100% of taxable income for taxable years beginning before 2021. In addition, the CARES Act allows NOLs incurred in 2018, 2019, and 2020 to be carried back to each of the five preceding taxable years to generate a refund of previously paid federal income taxes. The Company generated significant NOLs during 2018 and 2019 and filed carryback claims for these losses to the preceding five years. Accordingly, as of March 31, 2020, the Company recorded a federal income tax receivable of $15.0 million and an increase to its deferred tax liability of $10.1 million on its condensed balance sheet. During the third quarter of 2020, the Company received refunds corresponding to the 2018 NOL carryback, leaving a balance in the federal income tax receivable of $11.5 million at December 31, 2021. The income tax effects of temporary differences that give rise to significant portions of deferred income tax assets and (liabilities) as of December 31, 2021 and 2020, are as follows (in thousands): 2021 2020 Deferred income tax assets: Net operating loss $ 5,355 $ 3,361 Research and development credits 1,363 1,363 Stock compensation 114 175 Deferred compensation 632 705 Other 515 398 Total deferred income tax assets 7,979 6,002 Deferred income tax liabilities: Property and equipment (47,044) (47,626) Goodwill and other intangible assets (223) (266) Total deferred income tax liabilities (47,267) (47,892) Net deferred income tax liabilities $ (39,288) $ (41,890) As of December 31, 2021, the Company had NOL carryforwards for federal income tax purposes of $20.8 million, which may be carried forward indefinitely and can offset up to 80% of future taxable income in any given year. Future changes in ownership, as defined by Section 382 of the Internal Revenue Code ("IR"), could limit the amount of NOL carryforwards used in any one year. In general, under Section 382 and 383 of the IRC, a corporation that undergoes an “ownership change” is subject to limitations on its ability to utilize its pre-change NOLs and certain tax credits, to offset future taxable income and tax. In general, an ownership change occurs if the aggregate stock ownership of certain stockholders changes by more than 50 percentage points over such stockholders’ lowest percentage of ownership during the testing period (generally three years). We account for uncertain tax positions in accordance with guidance in FASB ASC 740, which prescribes the minimum recognition threshold a tax position taken or expected to be taken in a tax return is required to meet before being recognized in the financial statements. The Company assessed whether it had any uncertain tax positions related to open tax years and concluded there were none. Accordingly, no reserve for uncertain tax positions has been recorded as of December 31, 2021 and 2020. Our policy regarding income tax interest and penalties is to expense those items as incurred. During the years ended December 31, 2021 and 2020, there were no significant income tax interest or penalty items in the statement of operations.

Deferred Compensation Plans

Deferred Compensation Plans	12 Months Ended
	Dec. 31, 2021
Compensation Related Costs [Abstract]
Deferred Compensation Plans	Deferred Compensation Plans Effective January 1, 2016, the Company established a non-qualified deferred compensation plan for executive officers, directors and certain eligible employees. The assets of the deferred compensation plan are held in a rabbi trust and are subject to additional risk of loss in the event of bankruptcy or insolvency of the Company. The plan allows for deferral up to 90% of a participant’s base salary, bonus, commissions, director fees and restricted stock awards. A Company owned life insurance policy held in a rabbi trust is utilized as a source of funding for the plan. The cash surrender value of the life insurance policy is $2.5 million and $2.0 million as of December 31, 2021 and 2020, respectively, with a gain related to the policy of $298,000 and $168,000 reported in other income in our consolidated statement of operations for the year ended December 31, 2021 and 2020, respectively. For deferrals of base salary, bonus, commissions and director fees, settlement payments are made to participants in cash, either in a lump sum or in periodic installments. The deferred obligation to pay the deferred compensation and the deferred director fees is adjusted to reflect the positive or negative performance of investment measurement options selected by each participant and was $2.8 million and $2.2 million as of December 31, 2021 and 2020, respectively. The deferred obligation is included in other long-term liabilities in the consolidated balance sheets. For deferrals of restricted stock units, the plan does not allow for diversification, therefore, distributions are paid in shares of our common stock and the obligation is carried at grant value. As of December 31, 2021 and 2020, respectively, we

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2021
Equity [Abstract]
Stockholders' Equity	Stockholders' Equity Preferred Stock We have a total of 5.0 million authorized preferred shares which may be issued in series with rights and preferences as designated by the Board of Directors. As of December 31, 2021 and 2020, there were no issued or outstanding preferred shares.

Stock-Based and Other Long-Term

Stock-Based and Other Long-Term Incentive Compensation	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Stock-Based and Other Long-Term Incentive Compensation	Stock-Based and Other Long-Term Incentive Compensation Restricted Stock On June 20, 2019, at our annual meeting of shareholders, our shareholders approved an Equity Incentive Plan for restricted shares/units, stock options and other equity awards. The Equity Incentive Plan allows issuance up to 500,000 share of common stock. As of December 31, 2021, we had 276,319 shares outstanding under the Equity Incentive Plan that will vest over the next three years. As of December 31, 2021, 47,135 shares were still available for issuance under the Equity Incentive Plan. On March 18, 2021, the Compensation Committee awarded 129,212 shares of restricted common stock to two executive officers that vest ratably over three years, beginning on March 18, 2022. On June 17, 2021, the Compensation Committee awarded 5,000 shares of restricted common stock to an executive officer that vest ratably over three years beginning on June 17, 2022. In addition, on March 18, 2021, 5,612 shares of restricted common stock were awarded to each of our three independent Board members. Lastly, on April 1, 2021, 5,291 shares of restricted common stock were awarded to a newly appointed independent Board member. The restricted stock issued to our directors vests in one year from the date of grant. Compensation expense related to the restricted shares was approximately $1.7 million and $2.2 million for the years ended December 31, 2021 and 2020, respectively. As of December 31, 2021, there was a total of approximately $1.4 million of unrecognized compensation expense related to the unvested portion of these restricted shares/units. This expense is expected to be recognized over the next three years. A summary of all restricted stock activity as of December 31, 2020 and 2021 and changes during the years then ended are presented below. Number Grant Date Fair Value Weighted Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2019 279,766 $ 20.15 8.77 $ 3,430 Granted 123,185 $ 5.68 — $ 700 Vested (144,850) $ 20.82 — $ 946 Canceled/Forfeited — — — — Outstanding, December 31, 2020 258,101 $ 12.87 8.61 $ 2,447 Granted 156,339 $ 8.99 — $ 1,406 Vested (134,788) $ 14.94 — $ 1,258 Canceled/Forfeited (3333) $ 12.26 — $ 31 Outstanding, December 31, 2021 276,319 $ 9.67 1.77 $ 2,893 Other Long-Term Incentive Compensation On April 28, 2020, the Compensation Committee issued a long-term incentive award of $1.1 million to an executive officer that vests in equal, annual tranches over three years. At the time of vesting, each tranche will be payable in cash or common stock at the discretion of the Compensation Committee. On March 18, 2020, the Compensation Committee issued a long-term incentive award of $1.0 million to an executive officer that vests in equal, annual tranches over three years. In addition, on April 28, 2020, we issued a $50,000 award to each of our four independent members of our Board of Directors as partial payment for their services in 2020. These awards vest one year from the date of grant and are payable in cash upon vesting. On March 18, 2021, we issued a $50,000 award to each of our three independent Board members. On April 1, 2021, we issued a $50,000 award to a newly appointed independent Board member. These awards vest one year from the date of grant and are payable in cash upon vesting. The Company accounts for these other long-term incentive awards as liabilities under accrued liabilities on our condensed consolidated balance sheet. The vesting of these awards is subject to acceleration upon certain events, such as (i) death or disability of the recipient, (ii) certain circumstances in connection with a change of control of the Company, (iii) for executive officers, termination without cause (as defined in the agreement), and (iv) for executive officers, resignation for good reason (as defined). Total compensation expense related to these other long-term incentive awards was approximately $0.8 million for the year ended December 31, 2021. As of December 31, 2021 there was a total of $1.2 million of unrecognized compensation expense related to these other long-term incentive awards which is expected to be recognized over the next three years. Stock Option Plan Our Stock Option Plan, which is stockholder approved, permits the granting of stock options to its employees for up to 1.0 million shares of common stock. We believe that such awards align the interests of our employees with our stockholders. Option awards are generally granted with an exercise price equal to the market price of our stock at the date of grant; those option awards generally vest in equal increments over three years of continuous service and have ten-year contractual terms. Certain option and share awards provide for accelerated vesting if there is a change in control of the Company (as defined in the Stock Option Plan). The last date that grants can be made under the Stock Option Plan is February 28, 2026. As of December 31, 2021, 345,003 shares were still available to be granted under the Stock Option Plan. The fair value of each option award is estimated on the date of grant using the Black-Scholes option valuation model that uses the assumptions noted in the following table. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant. The expected life of options granted is based on the vesting period and historical exercise and post-vesting employment termination behavior for similar grants. We use historical data to estimate option exercise and employee termination within the valuation model; separate groups of employees that have similar historical exercise behavior are considered separately for valuation purposes. Weighted average Black -Scholes fair value assumption during the year ended December 31, are as follows: 2021 Risk free rate 1.45 % Expected life 6.86 Expected volatility 46.8 % Expected dividend yield — % During the year ended December 31, 2021, 55,500 stock option grants were made. A summary of all option activity as of December 31, 2020 and 2021 and changes during the years then ended are presented below: Number Weighted Average Weighted Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2019 208,334 $ 23.67 3.66 $ — Granted 5,000 $ 4.91 — — Exercised — — — — Canceled/Forfeited (12,000) $ 20.20 — $ 24 Expired (40,000) $ 19.11 — — Outstanding, December 31, 2020 161,334 $ 24.48 3.48 — Granted 55,500 $ 10.58 — — Exercised — — — — Canceled/Forfeited — — — — Expired (16,000) $ 17.81 — — Outstanding, December 31, 2021 200,834 $ 21.17 4.83 $ — Exercisable, December 31, 2021 145,334 $ 25.21 2.86 $ — The weighted average grant date fair value of options granted during 2021 was $5.15 per option. We had no grants in 2020. There were no option exercises in either 2021 or 2020. The following table summarizes information about our stock options outstanding at December 31, 2021: Range of Exercise Prices Options Outstanding Options Exercisable Shares Weighted Average Remaining Contractual Life (years) Weighted Average Exercise Price Shares Weighted Average Exercise Price $0.01-$18.00 64,000 8.68 $ 11.15 8,500 $ 14.89 $18.01-$22.00 20,500 1.22 18.75 20,500 $ 18.75 $22.01-$26.00 42,167 3.28 22.90 42,167 $ 22.90 $26.01-$30.00 30,000 5.13 28.15 30,000 $ 28.15 $30.01-$34.00 44,167 2.22 30.41 44,167 $ 30.41 200,834 4.83 $ 21.17 145,334 $ 25.21 The summary of the status of our unvested stock options as of December 31, 2021 and changes during the year then ended is presented below. Unvested stock options: Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2020 — $ — Granted 55,500 $ 10.58 Vested — — Canceled/Forfeited — — Unvested at December 31, 2021 55,500 $ 10.58 We recognized stock compensation expense from stock options vesting of $728 and $19,366 for the years ended

(Loss) Earnings per Share

(Loss) Earnings per Share	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
(Loss) Earnings per Share	(Loss) Earnings per Share Basic (loss) earnings per common share is computed using the weighted average number of common shares outstanding during the period. Diluted (loss) earnings per common share is computed using the weighted average number of common stock and common stock equivalent shares outstanding during the period. The following table sets forth the computation of basic and diluted (loss) earnings per share (in thousands, except per share amounts): Year Ended December 31, 2021 2020 Numerator: Net (loss) income $ (9,183) $ 1,808 Denominator for basic net (loss) income per common share: Weighted average common shares outstanding 13,100 13,224 Denominator for diluted net (loss) income per share: Weighted average common shares outstanding 13,100 13,224 Dilutive effect of stock options and restricted shares — 37 Diluted weighted average shares 13,100 13,261 (Loss) earnings per common share: Basic $ (0.70) $ 0.14 Diluted $ (0.70) $ 0.14 In the year ended ended December 31, 2021, 276,319 restricted stock/units and 200,834 stock options were not included in the computation of dilutive income per share, due to their anti-dilutive effect. In the year ended ended December 31, 2020, 221,061 restricted stock/units and 161,334 stock options were not included in the computation of diluted loss per share due to their antidilutive effect.

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2021
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal Proceedings From time to time, we are a party to various legal proceedings in the ordinary course of our business. While management is unable to predict the ultimate outcome of these actions, it believes that any ultimate liability arising from these actions will not have a material effect on our financial position, results of operations or cash flow. We are not currently a party to any bankruptcy, receivership, reorganization, adjustment or similar proceeding, and we are not aware of any other threatened litigation.

Subsequent Events

Subsequent Events	12 Months Ended
	Dec. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events None.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Principles of Consolidation	Principles of ConsolidationThe accompanying consolidated financial statements include the accounts of the Company, its subsidiary, NGSG Properties, LLC and the rabbi trust associated with the Company’s deferred compensation plan, see Note 10. All significant intercompany accounts and transactions for the periods presented have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of our consolidated financial statements in conformity with generally accepted accounting principles in the United States of America requires our management to make estimates and assumptions that affect the amounts reported in these consolidated financial statements and accompanying notes. Actual results could differ from those estimates. Significant estimates include fixed asset lives, bad debt allowance and the allowance for inventory obsolescence. Additionally, NGS conducts a yearly review of impairment of long-lived assets. Throughout the review, determining factors are based on estimates that can significantly impact the carrying value of these assets. It is at least reasonably possible these estimates could be revised in the near term and the revisions could be material.
Cash Equivalents and Financial Instruments	Cash Equivalents and Financial InstrumentsFor purposes of reporting cash flows, we consider all short-term investments with an original maturity of three months or less to be cash equivalents. We invest our cash primarily in deposits and money market funds with commercial banks.  At times, cash balances at banks and financial institutions may exceed federally insured amounts. We believe that the risk to our cash balance is minimal because we have chosen a large regional bank with strong long-term ratings of Baa3/BBB-.
Accounts Receivable	Accounts ReceivableOur trade receivables consist of customer obligations for the sale of compressors and flare systems due under normal trade terms, and operating leases for the use of our natural gas compressors. The receivables are not collateralized except as provided for under lease agreements. However, we typically require deposits of as much as 50% or use of progress payments for large custom sales contracts. We perform ongoing credit evaluations of our customers and adjust credit limits based on management's assessment of the customer's financial condition and payment history, as well as industry conditions and general economic conditions.  We continuously monitor collections and payments from our customers, and maintain a provision for estimated credit losses based upon our historical experience and any specific customer collection issues that we have identified.  While such credit losses have historically been within our expectations and the provisions established, we cannot guarantee that we will continue to experience the same credit loss rates that we have in the past.  One customer accounted for 46% and 35% of our accounts receivable as of December 31, 2021 and 2020, respectively.  A significant change in the liquidity or financial position of this customer could have a material adverse impact on the collectability of our accounts receivable and our future operating results.
Revenue Recognition Policy	Revenue Recognition Policy Revenue is measured based on a consideration specified in a customer’s contract, excluding any sale incentives and taxes collected on behalf of third parties (i.e. sales and property taxes). Revenue is recognized when a customer obtains control of promised goods or services in an amount that reflects the consideration that we expect to receive for those goods or services. To recognize revenue, we (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when, or as, we satisfy the performance obligation(s). Shipping and handling costs incurred are accounted for as fulfillment costs and are included in cost of revenues in our Consolidated Statements of Operations. Nature of Goods and Services The following is a description of principal activities from which the Company generates its revenue: Rental Revenue . The Company generates revenue from renting compressors and flare systems to our customers. These contracts, which all qualify as operating leases under ASC Topic 842, Leases (ASC 842), may also include a fee for servicing the compressor or flare during the rental contract. Our rental contracts typically range from six Sales Revenue. The Company generates revenue by the sale of custom/fabricated compressors, flare systems and parts, as well as, exchange/rebuilding customer owned compressors and sale of used rental equipment. Custom/fabricated compressors and flare systems - The Company designs and fabricates compressors and flares based on the customer’s specifications outlined in their contract. Though the equipment being built is customized by the customer, control under these contracts does not pass to the customer until the compressor or flare package is completed and shipped, or in accordance with a bill and hold arrangements the customer accepts title and assumes the risk and rewards of ownership. We request some of our customers to make progressive payments as the product is being built; these payments are recorded as a contract liability on the Deferred Income line on the consolidated balance sheet until control has been transferred. These contracts also may include an assurance warranty clause to guarantee the product is free from defects in material and workmanship for a set duration of time; this is a standard industry practice and is not considered a performance obligation. From time to time, upon the customer’s written request, we recognize revenue when manufacturing is complete and the equipment is ready for shipment. At the customer’s request, we will bill the customer upon completing all performance obligations, but before shipment. The customer will formally request we ship the equipment per their direction from our manufacturing facility at a later specified date and that we segregate the equipment from our finished goods, such that they are not available to fill other orders. Per the customer’s agreement change of control is passed to the customer once the equipment is complete and ready for shipment. We have operated using bill and hold agreements with certain customers for many years, with consistent satisfactory results for both the customer and us. The credit terms on these agreements are consistent with the credit terms on all other sales. All control is shouldered by the customer and there are no exceptions to the customer’s commitment to accept and pay for the manufactured equipment. Revenues recognized related to bill and hold arrangements for the years ended December 31, 2021 and 2020 was approximately $20,000 and $852,000, respectively. Parts - Revenue is recognized after the customer obtains control of the parts. Control is passed either by the customer taking physical possession or the parts being shipped. The amount of revenue recognized is not adjusted for expected returns, as our historical part returns have been de minimis. Exchange or rebuilding customer owned compressors - Based on the contract, the Company will either exchange a new/rebuilt compressor for the customer’s malfunctioning compressor or rebuild the customer’s compressor. Revenue is recognized after control of the replacement compressor has transferred to the customer based on the terms of the contract, i.e., by physical delivery, delivery and installment, or shipment of the compressor. Used compressors or flares - From time to time, a customer may request to purchase a used compressor or flare out of our rental fleet. Revenue from the sale of rental equipment is recognized when the control has passed to the customer based on the terms of the contract, i.e. when the customer has taken physical possession or the equipment has been shipped. Service and Maintenance Revenue. The Company provides routine or call-out services on customer owned equipment. Revenue is recognized after services in the contract are rendered. Payment terms for sales revenue and service and maintenance revenue discussed above are generally 30 to 60 days although terms for specific customers can vary. Also, the transaction prices are not subject to variable consideration constraints. Contract Costs The Company recognizes the incremental costs of obtaining contracts as an expense when incurred if the amortization period of the assets that the Company otherwise would have recognized is one year or less. These costs are included in selling, general and administrative expense on our Consolidated Statements of Operations.
Leases	Leases
Major Customers and Concentration of Credit Risk	Major Customers and Concentration of Credit RiskSales and rental income from Occidental Permian, LTD. ("Oxy") in 2021 and 2020 amounted to 40% and 30% of revenue, respectively. No other single customer accounted for more than 10% of our revenues in 2021 and 2020. Oxy's accounts receivable balances amounted to 46% and 35% of our accounts receivable as of December 31, 2021 and 2020, respectively. No other customers amounted to more than 10% of our accounts receivable as of December 31, 2021 and 2020.
Inventory	InventoryInventory (current and long-term) is valued at the lower of cost and net realizable value. The cost of inventories is determined by the weighted average method. We regularly review inventory quantities on hand and record a provision for excess and obsolete inventory based primarily on current and anticipated customer demand and production requirements. The Company assesses anticipated customer demand based on current and upcoming capital expenditure budgets of its major customers as well as other significant companies in the industry, along with oil and natural gas price forecasts and other factors affecting the industry. In addition, our long-term inventory consists of raw materials and replacement parts that remain viable but which the Company does not expect to sell within the next year.
Rental Equipment and Property and Equipment	Rental Equipment and Property and EquipmentRental equipment and property and equipment are recorded at cost less accumulated depreciation, except for work-in-progress on new rental equipment which is recorded at cost until it’s complete and added to the fleet. Depreciation is computed using the straight-line method over the estimated useful lives of the assets. Our rental equipment has an estimated useful life between 15 and 25 years, while our property and equipment has an estimate useful lives which range from 3 to 39 years.  The majority of our property and equipment, including rental equipment, is a direct cost to generating revenue.
Impairment of Rental Equipment	We assess the impairment of rental equipment and property and equipment whenever events or changes in circumstances indicate that the net recorded amount may not be recoverable. The following factors could trigger an impairment review: significant underperformance relative to historical or projected future cash flows; significant adverse changes in the extent or manner in which asset (or asset group) is being used or its condition, including a meaningful drop in fleet utilization over the prior four quarters; significant negative industry or company-specific trends or actions, including meaningful capital expenditure budget reductions by our major customers or other sizable exploration and production or midstream companies, as well as significant declines in oil and natural gas prices; legislative changes prohibiting us from leasing our units or flares; or poor general economic conditions. An impairment loss is recognized if the future undiscounted cash flows associated with the asset (or asset group) and the estimated fair value of the asset are less than the asset's carrying value. Sales of equipment out of the rental fleet are included with sales revenue and cost of sales, while retirements of units are shown a separate operating expense. Gains and losses resulting from sales and dispositions of other property and equipment are included with other income. Maintenance and repairs are charged to cost of rentals as incurred.
Intangibles	Intangibles At December 31, 2021 and 2020, NGS had intangible assets, which relate to developed technology and a trade name. Developed technology is amortized on a straight-line basis with a useful life of 20 years, with a weighted average remaining life of approximately four years as of December 31, 2021. NGS has an intangible asset related to the trade name of SCS which was acquired in our acquisition of Screw Compression Systems in January 2005. This asset is not being amortized as it has been deemed to have an indefinite life.
Warranty	WarrantyWhen warranted, we accrue amounts for estimated warranty claims based upon current and historical product warranty costs and any other related information known.
Income Taxes	Income Taxes Deferred tax assets and liabilities are recognized for the future tax consequences attributable to temporary differences between the financial statement carrying amounts of assets and liabilities and their respective tax bases, and operating losses and tax credit carry-forwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which those temporary differences are expected to be recovered or settled. We assess the likelihood that our deferred tax assets will be recovered from future taxable income and, to the extent we believe that recovery is not probable, we establish a valuation allowance. To the extent we establish a valuation allowance or increase this allowance in a period, we include an expense in the tax provision in the statement of income. ASC Topic 740 prescribes a recognition threshold and measurement attribute for the financial statement recognition and measurement of a tax position taken or expected to be taken in a tax return. In order to record any financial statement benefit, we are required to determine, based on technical merits of the position, whether it is more likely than not (a likelihood of more than 50 percent) that a tax position will be sustained upon examination, including resolution of any related appeals or litigation processes. If that step is satisfied, then we must measure the tax position to determine the amount of benefit to recognize in the financial statements. The tax position is measured at the largest amount of the benefit that is greater than 50 percent likely of being realized upon ultimate settlement. Our policy regarding income tax interest and penalties is to expense those items as other expense.
Fair Value Measurement	Fair Value Measurement Fair value is defined as the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date under current market conditions. ASC Topic 820 established a fair value hierarchy, which requires an entity to maximize the use of observable inputs when measuring fair value. These inputs are categorized as follows: Level 1- quoted prices in an active market for identical assets or liabilities; Level 2- quoted prices in an active market for similar assets or liabilities, inputs other than quoted prices that are observable for similar assets or liabilities, inputs derived principally from or corroborated by observable market data by correlation or other means; and Level 3- valuation methodology with unobservable inputs that are significant to the fair value measurement.
Segments and Related Information	Segments and Related Information ASC 280-10-50, “Operating Segments”, define the characteristics of an operating segment as a) being engaged in business activity from which it may earn revenue and incur expenses, b) being reviewed by the company's chief operating decision maker (CODM) for decisions about resources to be allocated and assess its performance and c) having discrete financial information. Although we indeed look at our products to analyze the nature of our revenue, other financial information, such as certain costs and expenses, net income and EBITDA are not captured or analyzed by these categories. Our CODM does not make resource allocation decisions or access the performance of the business based on these categories, but rather in the aggregate. Based on this, management believes that it operates in one business segment. We are engaged in the business of designing and manufacturing compressors and flares. Our compressors and flares are sold and rented to our customers. In addition, we provide service and maintenance on compressors in our fleet and to third parties. These business activities are similar in all geographic areas. Our manufacturing process is essentially the same for the entire Company and is performed in house at our facilities in Midland, Texas and Tulsa, Oklahoma. Our customers primarily consist of entities in the business of producing natural gas. The maintenance and service of our products is consistent across the entire Company and is performed via an internal fleet of vehicles. The regulatory environment is similar in every jurisdiction in that the most impacting regulations and practices are the result of federal energy policy.
Recently Issued Accounting Pronouncements	Recently Issued Accounting Pronouncements In March 2020, the FASB issued ASU 2020-04, Reference Rate Reform, which provides temporary optional guidance to companies impacted by the transition away from the London Interbank Offered Rate ("LIBOR"). The guidance provides certain expedients and exceptions to applying GAAP in order to lessen the potential accounting burden when contracts, hedging relationships and other transactions that reference LIBOR as a benchmark rate are modified. This guidance is effective upon issuance and expires on December 31, 2022. We are currently evaluating the impact of the LIBOR transition and this ASU 2020-04 on our consolidated financial statements.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2021
Accounting Policies [Abstract]
Schedule of Allowance for Doubtful Accounts	A summary of our allowance for doubtful accounts is as follows: Year Ended December 31, ($ in thousands) 2021 2020 Beginning balance $ 1,161 $ 918 Accruals 65 329 Recoveries 8 — Write-offs (105) (86) Ending balance $ 1,129 $ 1,161
Disaggregation of Revenue	The following table shows the Company's revenue disaggregated by product or service type for the years ended: Year Ended December 31, 2021 2020 (in thousands) Compressors - sales $ 1,891 $ 2,211 Flares - sales 365 489 Other (Parts/Rebuilds) - sales 4,626 2,957 Service and maintenance 1,914 1,572 Total revenue from contracts with customers 8,796 7,229 Add: ASC 842 rental revenue 63,624 60,826 Total revenue $ 72,420 $ 68,055
Contract with Customer, Asset and Liability	As of December 31, 2021 and 2020, we had the following receivables and deferred income from contracts with customers: December 31, 2021 2020 (in thousands) Accounts Receivable Accounts receivable - contracts with customers $ 3,354 $ 3,243 Accounts receivable - ASC 842 8,164 9,802 Total Accounts Receivable 11,518 13,045 Less: Allowance for doubtful accounts (1,129) (1,161) Total Accounts Receivable, net $ 10,389 $ 11,884 Deferred income $ 1,312 $ 1,103

Inventory (Tables)

Inventory (Tables)	12 Months Ended
	Dec. 31, 2021
Inventory Disclosure [Abstract]
Schedule of Inventory	Our inventory, net of allowance for obsolescence of $64,000 and $221,000 at December 31, 2021 and 2020, respectively, consisted of the following: December 31, 2021 2020 (in thousands) Raw materials - current $ 17,528 $ 18,026 Work-in-process 1,801 1,900 Inventory - current 19,329 19,926 Raw materials - long term (net of allowances of $64 and $221, respectively) 1,582 1,065 Inventory - total $ 20,911 $ 20,991 A summary of our inventory allowance is as follows: Year Ended December 31, 2021 2020 (in thousands) Beginning balance $ 221 $ 24 Accruals 208 251 Write-offs (365) (54) Ending balance $ 64 $ 221

Rental Equipment, Property an_2

Rental Equipment, Property and Equipment (Tables)	12 Months Ended
	Dec. 31, 2021
Property, Plant and Equipment [Abstract]
Schedule of Rental Equipment	Our rental equipment and associated accumulated depreciation as of December 31, 2021 and 2020, respectively, consisted of the following: December 31, 2021 2020 (in thousands) Compressor units $ 374,336 $ 379,623 Work-in-progress 5,212 3,764 Rental equipment 379,548 383,387 Accumulated depreciation (172,563) (175,802) Rental equipment, net of accumulated depreciation $ 206,985 $ 207,585 Property and equipment consists of the following at December 31, 2021 and 2020: December 31, Useful Lives (Years) 2021 2020 ($ in thousands) Land — $ 1,680 $ 1,680 Building 39 18,977 18,977 Leasehold improvements 39 1,197 1,168 Office equipment and furniture 5 2,016 2,016 Software 5 573 573 Machinery and equipment 7 3,874 3,653 Vehicles 3 8,295 7,598 Total 36,612 35,665 Less accumulated depreciation (15,784) (13,916) Total $ 20,828 $ 21,749 The following table depicts annual depreciation expense associated with each product line as well as our corporate activities at December 31, 2021 and 2020: December 31, 2021 2020 (in thousands) Rentals $ 24,423 $ 24,255 Sales 281 281 Service & Maintenance 49 42 Corporate 476 495 Total $ 25,229 $ 25,073

Rental Activity (Tables)

Rental Activity (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Schedule of Future Minimum Rent Payments Receivable	Future minimum rent payments for arrangements not on a month-to-month basis at December 31, 2021 are as follows: Years Ending December 31, (in thousands) 2022 $29,583 2023 18,684 2024 18,277 2025 8,739 2026 2,614 Thereafter 462 Total $78,359

Leases (Tables)

Leases (Tables)	12 Months Ended
	Dec. 31, 2021
Leases [Abstract]
Schedule of Balance Sheet Impact	: Classification on Consolidated December 31, Balance Sheets 2021 2020 ($ in thousands) Operating lease assets Right of use assets-operating leases $ 285 $ 483 Current lease liabilities Current operating leases $ 68 $ 198 Noncurrent lease liabilities Long-term operating leases 217 285 Total lease liabilities $ 285 $ 483 Weighted average remaining lease term in years 6.6 1.5 Implicit Rate 3.4 % 3.2 %
Schedule of Cash Flow Impact	December 31, 2021 2020 (in thousands) Cash paid for amounts included in the measurement of lease liabilities Operating lease cost (1) (2) $ 556 $ 550 (1) Lease costs are classified on the Consolidated Statements of Operations in cost of sales, cost of compressors and selling, general and administrative expenses. (2) Includes costs of $346,000 for leases with terms of 12 months or less and $210,000 for leases with terms greater than 12 months for the year ended December 31, 2021. Includes costs of $333,000 for leases with terms of 12 months or less and $217,000 for leases with terms greater than 12 months for the year ended December 31, 2020.
Schedule of Future Maturities of Lease Liabilities	The following table shows the future maturities of lease liabilities: Years Ending December 31, Lease Liabilities (in thousands) 2022 $ 77 2023 38 2024 38 2025 38 2026 38 Thereafter 92 Total lease payments 321 Less: Imputed interest (36) Total $ 285

Intangibles (Tables)

Intangibles (Tables)	12 Months Ended
	Dec. 31, 2021
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Identified Finite-Lived Intangible Assets, Finite Lived	The following table represents the identified intangible assets by major asset class (in thousands): December 31, 2021 December 31, 2020 Useful Life (years) Gross Carrying Value Accumulated Amortization Net Book Value Gross Carrying Value Accumulated Amortization Net Book Value Developed Technology 20 $ 2,505 $ 2,134 $ 371 $ 2,505 $ 2,008 $ 497 Trade Name Indefinite 654 — 654 654 — 654 Total $ 3,159 $ 2,134 $ 1,025 $ 3,159 $ 2,008 $ 1,151
Schedule of Identified Indefinite-Lived Intangible Assets	The following table represents the identified intangible assets by major asset class (in thousands): December 31, 2021 December 31, 2020 Useful Life (years) Gross Carrying Value Accumulated Amortization Net Book Value Gross Carrying Value Accumulated Amortization Net Book Value Developed Technology 20 $ 2,505 $ 2,134 $ 371 $ 2,505 $ 2,008 $ 497 Trade Name Indefinite 654 — 654 654 — 654 Total $ 3,159 $ 2,134 $ 1,025 $ 3,159 $ 2,008 $ 1,151

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Provision for Income Taxes	The (provision for) benefit from income taxes for the years ended December 31, 2021 and 2020, consists of the following (in thousands): 2021 2020 Current benefit: Federal benefit $ — $ 15,587 State (expense) benefit 1 (149) Total current benefit 1 15,438 Deferred benefit: Federal benefit (expense) 1,991 (10,234) State benefit (expense) 611 (412) Total deferred benefit (expense) 2,602 (10,646) Total benefit $ 2,603 $ 4,792
Effective Income Tax Rate Reconciliation	The effective tax rate for the years ended December 31, 2021 and 2020, differs from the statutory rate as follows: 2021 2020 Statutory rate 21.0 % 21.0 % State and local taxes 5.2 % (17) % Stock based compensation (0.7) % (13.1) % Nondeductible compensation (3.6) % (11.6) % Effect of CARES Act — % 180.3 % Other 0.2 % 0.5 % Effective rate 22.1 % 160.1 % Effective rate 22.1 % 160.1 %
Deferred Tax Assets and Liabilities	The income tax effects of temporary differences that give rise to significant portions of deferred income tax assets and (liabilities) as of December 31, 2021 and 2020, are as follows (in thousands): 2021 2020 Deferred income tax assets: Net operating loss $ 5,355 $ 3,361 Research and development credits 1,363 1,363 Stock compensation 114 175 Deferred compensation 632 705 Other 515 398 Total deferred income tax assets 7,979 6,002 Deferred income tax liabilities: Property and equipment (47,044) (47,626) Goodwill and other intangible assets (223) (266) Total deferred income tax liabilities (47,267) (47,892) Net deferred income tax liabilities $ (39,288) $ (41,890)

Stock-Based and Other Long-Te_2

Stock-Based and Other Long-Term Incentive Compensation (Tables)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Summary of Restricted Stock Activity	A summary of all restricted stock activity as of December 31, 2020 and 2021 and changes during the years then ended are presented below. Number Grant Date Fair Value Weighted Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2019 279,766 $ 20.15 8.77 $ 3,430 Granted 123,185 $ 5.68 — $ 700 Vested (144,850) $ 20.82 — $ 946 Canceled/Forfeited — — — — Outstanding, December 31, 2020 258,101 $ 12.87 8.61 $ 2,447 Granted 156,339 $ 8.99 — $ 1,406 Vested (134,788) $ 14.94 — $ 1,258 Canceled/Forfeited (3333) $ 12.26 — $ 31 Outstanding, December 31, 2021 276,319 $ 9.67 1.77 $ 2,893
Stock Options Fair Value Assumptions	The fair value of each option award is estimated on the date of grant using the Black-Scholes option valuation model that uses the assumptions noted in the following table. The risk-free rate for periods within the contractual life of the option is based on the U.S. Treasury yield curve in effect at the time of grant. The expected life of options granted is based on the vesting period and historical exercise and post-vesting employment termination behavior for similar grants. We use historical data to estimate option exercise and employee termination within the valuation model; separate groups of employees that have similar historical exercise behavior are considered separately for valuation purposes. Weighted average Black -Scholes fair value assumption during the year ended December 31, are as follows: 2021 Risk free rate 1.45 % Expected life 6.86 Expected volatility 46.8 % Expected dividend yield — %
Summary of Option Activity	A summary of all option activity as of December 31, 2020 and 2021 and changes during the years then ended are presented below: Number Weighted Average Weighted Aggregate Intrinsic Value (in thousands) Outstanding, December 31, 2019 208,334 $ 23.67 3.66 $ — Granted 5,000 $ 4.91 — — Exercised — — — — Canceled/Forfeited (12,000) $ 20.20 — $ 24 Expired (40,000) $ 19.11 — — Outstanding, December 31, 2020 161,334 $ 24.48 3.48 — Granted 55,500 $ 10.58 — — Exercised — — — — Canceled/Forfeited — — — — Expired (16,000) $ 17.81 — — Outstanding, December 31, 2021 200,834 $ 21.17 4.83 $ — Exercisable, December 31, 2021 145,334 $ 25.21 2.86 $ —
Summary of Stock Options Outstanding	The following table summarizes information about our stock options outstanding at December 31, 2021: Range of Exercise Prices Options Outstanding Options Exercisable Shares Weighted Average Remaining Contractual Life (years) Weighted Average Exercise Price Shares Weighted Average Exercise Price $0.01-$18.00 64,000 8.68 $ 11.15 8,500 $ 14.89 $18.01-$22.00 20,500 1.22 18.75 20,500 $ 18.75 $22.01-$26.00 42,167 3.28 22.90 42,167 $ 22.90 $26.01-$30.00 30,000 5.13 28.15 30,000 $ 28.15 $30.01-$34.00 44,167 2.22 30.41 44,167 $ 30.41 200,834 4.83 $ 21.17 145,334 $ 25.21
Summary of the Status of Unvested Stock Options	The summary of the status of our unvested stock options as of December 31, 2021 and changes during the year then ended is presented below. Unvested stock options: Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2020 — $ — Granted 55,500 $ 10.58 Vested — — Canceled/Forfeited — — Unvested at December 31, 2021 55,500 $ 10.58

(Loss) Earnings per Share (Tabl

(Loss) Earnings per Share (Tables)	12 Months Ended
	Dec. 31, 2021
Earnings Per Share [Abstract]
Computation of Basic and Diluted Earnings Per Share	The following table sets forth the computation of basic and diluted (loss) earnings per share (in thousands, except per share amounts): Year Ended December 31, 2021 2020 Numerator: Net (loss) income $ (9,183) $ 1,808 Denominator for basic net (loss) income per common share: Weighted average common shares outstanding 13,100 13,224 Denominator for diluted net (loss) income per share: Weighted average common shares outstanding 13,100 13,224 Dilutive effect of stock options and restricted shares — 37 Diluted weighted average shares 13,100 13,261 (Loss) earnings per common share: Basic $ (0.70) $ 0.14 Diluted $ (0.70) $ 0.14

Summary of Significant Accoun_4

Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)segment	Dec. 31, 2020USD ($)
Revenue from External Customer [Line Items]
Cash equivalents, qualification, maximum original maturity of short-term investments	3 months
Customer deposit requirements, large custom contracts, maximum percentage	50.00%
Allowance for doubtful accounts	$ 1,129	$ 1,161
Revenues	72,420	68,055
Revenue recognized	$ 1,100	73
Amortization period of capitalized contract costs	1 year
Product warranty reserves	$ 0	$ 0
Uncertain tax positions	$ 0
Number of business segments | segment	1
Developed Technology
Revenue from External Customer [Line Items]
Intangible assets, useful life	20 years	20 years
Intangible assets, weighted average remaining life	4 years
Bill and Hold Arrangement
Revenue from External Customer [Line Items]
Revenues	$ 20	$ 852
Minimum
Revenue from External Customer [Line Items]
Rental contract term	6 months
Property and equipment, estimated useful life	3 years
Maximum
Revenue from External Customer [Line Items]
Rental contract term	60 months
Property and equipment, estimated useful life	39 years
Rental Contracts, Excluding Large Horsepower Compressors | Minimum
Revenue from External Customer [Line Items]
Rental contract term	6 months
Rental Contracts, Excluding Large Horsepower Compressors | Maximum
Revenue from External Customer [Line Items]
Rental contract term	24 months
Rental Contracts, Large Horsepower Compressors | Maximum
Revenue from External Customer [Line Items]
Rental contract term	60 months
Customer Concentration Risk | Oxy | Sales and Rental Income
Revenue from External Customer [Line Items]
Concentration risk, percentage	40.00%	30.00%
Customer Concentration Risk | Oxy | Accounts Receivable
Revenue from External Customer [Line Items]
Concentration risk, percentage	46.00%	35.00%

Summary of Significant Accoun_5

Summary of Significant Accounting Policies - Schedule of Allowance for Doubtful Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Accounts Receivable, Allowance for Credit Loss [Roll Forward]
Beginning balance	$ 1,161	$ 918
Accruals	65	329
Recoveries	8	0
Write-offs	(105)	(86)
Ending balance	$ 1,129	$ 1,161

Summary of Significant Accoun_6

Summary of Significant Accounting Policies - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 8,796	$ 7,229
Add: ASC 842 rental revenue	63,624	60,826
Total revenue	72,420	68,055
Compressors - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	1,891	2,211
Flares - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	365	489
Other (Parts/Rebuilds) - sales
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	4,626	2,957
Service and maintenance
Disaggregation of Revenue [Line Items]
Revenue from contracts with customers	$ 1,914	$ 1,572

Summary of Significant Accoun_7

Summary of Significant Accounting Policies - Contract Balances (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Accounts Receivable
Accounts receivable - contracts with customers	$ 3,354	$ 3,243
Accounts receivable - ASC 842	8,164	9,802
Total Accounts Receivable	11,518	13,045
Less: Allowance for doubtful accounts	(1,129)	(1,161)
Total Accounts Receivable, net	10,389	11,884
Deferred income	$ 1,312	$ 1,103

Inventory - Narrative (Details)

Inventory - Narrative (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Allowance for inventory obsolescence	$ 64	$ 221	$ 24

Inventory - Schedule of Invento

Inventory - Schedule of Inventory (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Inventory Disclosure [Abstract]
Raw materials - current	$ 17,528	$ 18,026
Work-in-process	1,801	1,900
Inventory - current	19,329	19,926
Raw materials - long term (net of allowances of $64 and $221, respectively)	1,582	1,065
Allowance for inventory obsolescence	64	221	$ 24
Inventory - total	$ 20,911	$ 20,991

Inventory - Schedule of Inven_2

Inventory - Schedule of Inventory Allowance (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Inventory Valuation Reserves [Roll Forward]
Beginning balance	$ 221	$ 24
Accruals	208	251
Write-offs	(365)	(54)
Ending balance	$ 64	$ 221

Rental Equipment, Property an_3

Rental Equipment, Property and Equipment - Schedule of Rental Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Rental equipment	$ 379,548	$ 383,387
Accumulated depreciation	(172,563)	(175,802)
Rental equipment, net of accumulated depreciation	206,985	207,585
Rental Compressor Unit
Property, Plant and Equipment [Line Items]
Rental equipment	374,336	379,623
Work-in-progress
Property, Plant and Equipment [Line Items]
Rental equipment	$ 5,212	$ 3,764

Rental Equipment, Property an_4

Rental Equipment, Property and Equipment - Narrative (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2021USD ($)compressor	Dec. 31, 2020USD ($)compressor
Property, Plant and Equipment [Line Items]
Depreciation | $	$ 25,229	$ 25,073
Number of units retired | compressor	263
Retirement of rental equipment | $	$ 3,096	291
Rental Equipment
Property, Plant and Equipment [Line Items]
Depreciation | $	$ 22,900	22,700
Number of rental fleet | compressor	65
Number of repurchased from customer | compressor	35
Property, Plant, and Equipment, Excluding Rental Equipment
Property, Plant and Equipment [Line Items]
Depreciation | $	$ 2,400	$ 2,300
Rental Compressor Unit
Property, Plant and Equipment [Line Items]
Number of units retired | compressor		216
Minimum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	3 years
Minimum | Rental Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	15 years
Maximum
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	39 years
Maximum | Rental Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	25 years

Rental Equipment, Property an_5

Rental Equipment, Property and Equipment - Schedule of Rental Equipment, Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 36,612	$ 35,665
Less accumulated depreciation	(15,784)	(13,916)
Property and equipment, net	20,828	21,749
Land
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,680	1,680
Building
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	39 years
Property and equipment, gross	$ 18,977	18,977
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	39 years
Property and equipment, gross	$ 1,197	1,168
Office equipment and furniture
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	5 years
Property and equipment, gross	$ 2,016	2,016
Software
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	5 years
Property and equipment, gross	$ 573	573
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	7 years
Property and equipment, gross	$ 3,874	3,653
Vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, estimated useful life	3 years
Property and equipment, gross	$ 8,295	$ 7,598

Rental Equipment, Property an_6

Rental Equipment, Property and Equipment - Depreciation Expense by Product Line (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Depreciation	$ 25,229	$ 25,073
Corporate
Property, Plant and Equipment [Line Items]
Depreciation	476	495
Rentals | Operating Segments
Property, Plant and Equipment [Line Items]
Depreciation	24,423	24,255
Sales | Operating Segments
Property, Plant and Equipment [Line Items]
Depreciation	281	281
Service & Maintenance | Operating Segments
Property, Plant and Equipment [Line Items]
Depreciation	$ 49	$ 42

Rental Activity (Details)

Rental Activity (Details) $ in Thousands	Dec. 31, 2021USD ($)
Operating Leases, Future Minimum Payments Receivable [Abstract]
2022	$ 29,583
2023	18,684
2024	18,277
2025	8,739
2026	2,614
Thereafter	462
Total	$ 78,359
Minimum
Property Subject to or Available for Operating Lease [Line Items]
Rental contract term	6 months
Maximum
Property Subject to or Available for Operating Lease [Line Items]
Rental contract term	60 months

Leases - Narrative (Details)

Leases - Narrative (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 556	$ 550
Operating lease, cost	$ 210	$ 217
Minimum
Lessee, Lease, Description [Line Items]
Remaining lease term	1 year
Maximum
Lessee, Lease, Description [Line Items]
Remaining lease term	8 years

Leases - Balance Sheet Impact (

Leases - Balance Sheet Impact (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Right of use assets-operating leases	$ 285	$ 483
Current operating leases	68	198
Long-term operating leases	217	285
Total lease liabilities	$ 285	$ 483
Weighted average remaining lease term in years	6 years 7 months 6 days	1 year 6 months
Implicit Rate	3.40%	3.20%

Leases - Cash Flow Impact (Deta

Leases - Cash Flow Impact (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
Operating lease cost	$ 556	$ 550
Short-term lease cost	346	333
Operating lease, cost	$ 210	$ 217

Leases - Future Maturities of L

Leases - Future Maturities of Lease Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Leases [Abstract]
2022	$ 77
2023	38
2024	38
2025	38
2026	38
Thereafter	92
Total lease payments	321
Less: Imputed interest	(36)
Total	$ 285	$ 483

Intangibles (Details)

Intangibles (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Intangible Assets [Line Items]
Amortization expense	$ 125	$ 125
Finite-Lived Intangible Assets, Net, Amortization Expense, Fiscal Year Maturity [Abstract]
2022	125
2023	125
2024	125
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	3,159	3,159
Accumulated Amortization	2,134	2,008
Net Book Value	1,025	1,151
Impairment of intangible assets	0	0
Trade Name
Finite-Lived Intangible Assets, Net [Abstract]
Gross Carrying Value	654	654
Accumulated Amortization	0	0
Net Book Value	$ 654	$ 654
Developed Technology
Finite-Lived Intangible Assets, Net [Abstract]
Intangible assets, useful life	20 years	20 years
Gross Carrying Value	$ 2,505	$ 2,505
Accumulated Amortization	2,134	2,008
Net Book Value	$ 371	$ 497

Credit Facility (Details)

Credit Facility (Details) $ in Thousands	May 11, 2021USD ($)	Dec. 31, 2021USD ($)	Dec. 31, 2020USD ($)
Line of Credit Facility [Line Items]
Line of credit		$ 0	$ 417
Revolving Credit Facility
Line of Credit Facility [Line Items]
Aggregate credit agreement commitment	$ 30,000	30,000
Debt term	5 years
Borrowing base amount available	$ 20,000	$ 20,000
Potential increase in borrowing capacity	30,000
Potential maximum borrowing capacity	$ 50,000
Borrowing base, component, percentage of eligible accounts receivable	90.00%
Percentage of eligible non investment grade decors	85.00%
Percentage of eligible inventory	50.00%
Line of credit facility, non exceeding cap of components	$ 2,000
Percentage of eligible compressors for extension of credit	95.00%
Term For depreciation	25 years
Percentage of net liquidation value of eligible compressors for extension of credit	80.00%
Percentage of eligible value at cost	80.00%
Commitment fee percentage	0.25%
Maximum leverage ratio allowed		3
Fixed charge coverage ratio	1
Revolving Credit Facility | Maximum
Line of Credit Facility [Line Items]
Default trigger, certain defaults of other company indebtedness, amount		$ 1,000
Default trigger, rendering of certain judgments, amount		$ 1,000
Revolving Credit Facility | Federal Fund Rate
Line of Credit Facility [Line Items]
Variable rate, applicable margin	0.50%
Revolving Credit Facility | Eurodollar Rate
Line of Credit Facility [Line Items]
Variable rate, applicable margin	1.00%
Revolving Credit Facility | Eurodollar Rate | Minimum
Line of Credit Facility [Line Items]
Variable rate, applicable margin	1.25%
Revolving Credit Facility | Eurodollar Rate | Maximum
Line of Credit Facility [Line Items]
Variable rate, applicable margin	1.75%
Revolving Credit Facility | Base Rate Loans | Minimum
Line of Credit Facility [Line Items]
Variable rate, applicable margin	0.25%
Revolving Credit Facility | Base Rate Loans | Maximum
Line of Credit Facility [Line Items]
Variable rate, applicable margin	0.75%

Income Taxes - Components of Pr

Income Taxes - Components of Provision for Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Current benefit:
Federal benefit	$ 0	$ 15,587
State (expense) benefit	1	(149)
Total current benefit	1	15,438
Deferred benefit:
Federal benefit (expense)	1,991	(10,234)
State benefit (expense)	611	(412)
Total deferred benefit (expense)	2,602	(10,646)
Total income tax benefit	$ 2,603	$ 4,792

Income Taxes - Income Tax Recon

Income Taxes - Income Tax Reconciliation (Details)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Statutory rate	21.00%	21.00%
State and local taxes	5.20%	(17.00%)
Stock based compensation	(0.70%)	(13.10%)
Nondeductible compensation	(3.60%)	(11.60%)
Effect of CARES Act	0.00%	180.30%
Other	0.20%	0.50%
Effective rate	22.10%	160.10%

Income Taxes - Narrative (Detai

Income Taxes - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal income tax receivable	$ 15,000	$ 11,538	$ 11,538
Deferred tax liability increase due to tax law change	$ 10,100
Net operating loss carryforward		20,800
Amount of reserve for uncertain tax positions		$ 0	$ 0

Income Taxes - Components of De

Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Deferred income tax assets:
Net operating loss	$ 5,355	$ 3,361
Research and development credits	1,363	1,363
Stock compensation	114	175
Deferred compensation	632	705
Other	515	398
Total deferred income tax assets	7,979	6,002
Deferred income tax liabilities:
Property and equipment	(47,044)	(47,626)
Goodwill and other intangible assets	(223)	(266)
Total deferred income tax liabilities	(47,267)	(47,892)
Net deferred income tax liabilities	$ (39,288)	$ (41,890)

Deferred Compensation Plans (De

Deferred Compensation Plans (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Compensation Related Costs [Abstract]
Participant's maximum compensation deferral percentage	90.00%
Company owned life insurance	$ 2,500	$ 2,000
Gain (loss) on company owned life insurance	298	168
Deferred compensation obligation	$ 2,800	$ 2,200
Deferred restricted stock shares (in shares)	17,248	45,998
Deferred compensation arrangement with individual, shares issued (in shares)	174,452	145,702
Deferred compensation arrangement, fair value of shares issued	$ 2,500	$ 2,200

Stockholders' Equity (Details)

Stockholders' Equity (Details) - shares	Dec. 31, 2021	Dec. 31, 2020
Equity [Abstract]
Preferred stock, shares authorized (in shares)	5,000,000	5,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Stock-Based and Other Long-Te_3

Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock Narrative (Details) - Restricted Stock $ in Millions	Jun. 17, 2021shares	Apr. 01, 2021shares	Mar. 18, 2021independent_directorexecutive_officershares	Dec. 31, 2021USD ($)shares	Dec. 31, 2020USD ($)shares	Dec. 31, 2019shares	Jun. 20, 2019shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding (in shares)				276,319	258,101	279,766
Granted (in shares)				156,339	123,185
Stock based compensation expense | $				$ 1.7	$ 2.2
Total unrecognized compensation expense | $				$ 1.4
Recognition period				3 years
Chief Financial Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			129,212
Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years		3 years
Number of executive officers | executive_officer			2
Vice President of Technical Services
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	5,000
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period				1 year
Granted (in shares)		5,291	5,612
Number of independent directors | independent_director			3
Equity Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)							500,000
Shares outstanding (in shares)				276,319
Award vesting period				3 years
2009 Restricted Stock/Units Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance under the equity incentive plan (in shares)				47,135

Stock-Based and Other Long-Te_4

Stock-Based and Other Long-Term Incentive Compensation - Restricted Stock Activity (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number  of Shares
Outstanding, beginning of period (in shares)	258,101	279,766
Granted (in shares)	156,339	123,185
Vested (in shares)	(134,788)	(144,850)
Canceled/Forfeited (in shares)	(3,333)	0
Outstanding, beginning of period (in shares)	276,319	258,101	279,766
Grant Date Fair Value
Outstanding, beginning of period (in dollars per share)	$ 12.87	$ 20.15
Granted (in dollars per share)	8.99	5.68
Vested (in dollars per share)	14.94	20.82
Canceled/Forfeited (in dollars per share)	12.26	0
Outstanding, end of period (in dollars per share)	$ 9.67	$ 12.87	$ 20.15
Weighted Average Remaining Contractual Life (years)
Weighted average remaining contractual life (years)	1 year 9 months 7 days	8 years 7 months 9 days	8 years 9 months 7 days
Aggregate Intrinsic Value
Outstanding	$ 2,893	$ 2,447	$ 3,430
Granted	1,406	700
Vested	1,258	$ 946
Cancelled/Forfeited	$ 31

Stock-Based and Other Long-Te_5

Stock-Based and Other Long-Term Incentive Compensation - Other Long-Term Incentive Compensation Narrative (Details) - Other Long-Term Incentive Compensation $ in Thousands	Apr. 01, 2021USD ($)	Mar. 18, 2021USD ($)independent_director	Apr. 28, 2020USD ($)independent_director	Mar. 18, 2020USD ($)	Dec. 31, 2021USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted			$ 1,100	$ 1,000
Award vesting period			3 years	3 years
Stock based compensation expense					$ 800
Total unrecognized compensation expense					$ 1,200
Recognition period					3 years
Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted	$ 50	$ 50	$ 50
Award vesting period		1 year	1 year
Number of independent directors | independent_director		3	4

Stock-Based and Other Long-Te_6

Stock-Based and Other Long-Term Incentive Compensation - Stock Options Narrative (Details) - USD ($)	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Jun. 16, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)	55,500	5,000
Weighted average grant date fair value of options granted (in dollars per share)	$ 10.58
Unrecognized compensation cost related to stock options	$ 247,000
Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average grant date fair value of options granted (in dollars per share)	$ 5.15	$ 0
Total intrinsic value of options exercised	$ 0	$ 0
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock based compensation expense	$ 728	$ 19,366
Stock Options | Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period	3 years
Award expiration period	10 years
Stock Options | Stock Option Plan | Common Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares authorized (in shares)			1,000,000
Number of shares available for grant (in shares)	345,003

Stock-Based and Other Long-Te_7

Stock-Based and Other Long-Term Incentive Compensation - Valuation Assumptions (Details)	12 Months Ended
	Dec. 31, 2021
Share-based Payment Arrangement [Abstract]
Risk free rate	1.45%
Expected life	6 years 10 months 9 days
Expected volatility	46.80%
Expected dividend yield	0.00%

Stock-Based and Other Long-Te_8

Stock-Based and Other Long-Term Incentive Compensation - Stock Option Activity (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Number  of Shares
Outstanding, beginning of period (in shares)	161,334	208,334
Granted (in shares)	55,500	5,000
Exercised (in shares)	0	0
Canceled/Forfeited (in shares)	0	(12,000)
Expired (in shares)	(16,000)	(40,000)
Outstanding, end of period (in shares)	200,834	161,334	208,334
Exercisable (in shares)	145,334
Weighted Average Exercise Price
Outstanding, beginning of period (in dollars per share)	$ 24.48	$ 23.67
Granted (in dollars per share)	10.58	4.91
Exercised (in dollars per share)	0	0
Canceled/Forfeited, weighted average exercise price (in dollars per share)	0	20.20
Expired (in dollars per share)	17.81	19.11
Outstanding, end of period (in dollars per share)	21.17	$ 24.48	$ 23.67
Exercisable (in dollars per share)	$ 25.21
Weighted Average Remaining Contractual Life (years)
Outstanding, weighted average remaining contractual life	4 years 9 months 29 days	3 years 5 months 23 days	3 years 7 months 28 days
Exercisable, weighted average remaining contractual life	2 years 10 months 9 days
Aggregate Intrinsic Value
Outstanding, aggregate intrinsic value	$ 0	$ 0	$ 0
Canceled/Forfeited, aggregate intrinsic value		$ 24
Exercisable, aggregate intrinsic value	$ 0

Stock-Based and Other Long-Te_9

Stock-Based and Other Long-Term Incentive Compensation - Stock Options by Exercise Price Range (Details)	12 Months Ended
	Dec. 31, 2021$ / sharesshares
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Options outstanding, shares (in shares) | shares	200,834
Options outstanding, weighted average remaining contractual life (years)	4 years 9 months 29 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 21.17
Options exercisable, shares (in shares) | shares	145,334
Options exercisable, weighted average exercise price (in dollars per share)	$ 25.21
$0.01-$18.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower limit (in dollars per share)	0.01
Range of exercise prices, upper limit (in dollars per share)	$ 18
Options outstanding, shares (in shares) | shares	64,000
Options outstanding, weighted average remaining contractual life (years)	8 years 8 months 4 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 11.15
Options exercisable, shares (in shares) | shares	8,500
Options exercisable, weighted average exercise price (in dollars per share)	$ 14.89
$18.01-$22.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower limit (in dollars per share)	18.01
Range of exercise prices, upper limit (in dollars per share)	$ 22
Options outstanding, shares (in shares) | shares	20,500
Options outstanding, weighted average remaining contractual life (years)	1 year 2 months 19 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 18.75
Options exercisable, shares (in shares) | shares	20,500
Options exercisable, weighted average exercise price (in dollars per share)	$ 18.75
$22.01-$26.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower limit (in dollars per share)	22.01
Range of exercise prices, upper limit (in dollars per share)	$ 26
Options outstanding, shares (in shares) | shares	42,167
Options outstanding, weighted average remaining contractual life (years)	3 years 3 months 10 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 22.90
Options exercisable, shares (in shares) | shares	42,167
Options exercisable, weighted average exercise price (in dollars per share)	$ 22.90
$26.01-$30.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower limit (in dollars per share)	26.01
Range of exercise prices, upper limit (in dollars per share)	$ 30
Options outstanding, shares (in shares) | shares	30,000
Options outstanding, weighted average remaining contractual life (years)	5 years 1 month 17 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 28.15
Options exercisable, shares (in shares) | shares	30,000
Options exercisable, weighted average exercise price (in dollars per share)	$ 28.15
$30.01-$34.00
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]
Range of exercise prices, lower limit (in dollars per share)	30.01
Range of exercise prices, upper limit (in dollars per share)	$ 34
Options outstanding, shares (in shares) | shares	44,167
Options outstanding, weighted average remaining contractual life (years)	2 years 2 months 19 days
Options outstanding, weighted average exercise price (in dollars per share)	$ 30.41
Options exercisable, shares (in shares) | shares	44,167
Options exercisable, weighted average exercise price (in dollars per share)	$ 30.41

Stock-Based and Other Long-T_10

Stock-Based and Other Long-Term Incentive Compensation - Summary of Unvested Stock Options (Details) - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Shares
Unvested, beginning of period (in shares)	0
Granted (in shares)	55,500	5,000
Vested (in shares)	0
Canceled/Forfeited (in shares)	0
Unvested, end of period (in shares)	55,500	0
Weighted Average Grant Date Fair Value
Unvested, beginning of period (in dollars per share)	$ 0
Granted (in dollars per share)	10.58
Vested (in dollars per share)	0
Canceled/Forfeited (in dollars per share)	0
Unvested, end of period (in dollars per share)	$ 10.58	$ 0

(Loss) Earnings per Share (Deta

(Loss) Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Numerator:
Net loss	$ (9,183)	$ 1,808
Denominator for basic net (loss) income per common share:
Weighted average common shares outstanding (in shares)	13,100,000	13,224,000
Denominator for diluted net (loss) income per share:
Dilutive effect of stock options and restricted shares (in shares)	0	37,000
Weighted average common shares outstanding, Diluted (in shares)	13,100,000	13,261,000
(Loss) earnings per common share:
Basic (in dollars per share)	$ (0.70)	$ 0.14
Diluted (in dollars per share)	$ (0.70)	$ 0.14
Restricted Stock/Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	276,319	221,061
Stock Options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Anti-dilutive securities (in shares)	200,834	161,334