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Summary of Significant Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2018
Accounting Policies [Abstract] |
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, |  |  |  |
| (in thousands) |  |  |  |
| 2018 |  | 2017 |  | 2016
Compressors - sales | $ | 10,994 |  | $ | 13,382 |  | $ | 10,038
Flares - sales | 2,535 |  | 2,755 |  | 1,183
Other (Parts/Rebuilds) - sales | 2,740 |  | 4,071 |  | 2,400
Service and maintenance 1 | 20,537 |  | 19,857 |  | 24,016
Total revenue from contracts with customers | 36,806 |  | 40,065 |  | 37,637
Add: non-ASC 606 rental revenue | 28,672 |  | 27,628 |  | 34,017
Total revenue | $ | 65,478 |  | $ | 67,693 |  | $ | 71,654
1Service and maintenance includes revenue from servicing our own rental equipment contracted to customers and third party equipment.
Contract with Customer, Asset and Liability | As of December 31, 2018 and December 31, 2017, we had the following receivables and deferred income from contracts with customers:
| December 31, 2018 |  | December 31, 2017
| (in thousands) |  |
Accounts Receivable |  |  |
Accounts receivable - contracts with customers | $ | 4,353 |  | $ | 5,454
Accounts receivable - non-ASC 606 | 3,157 |  | 3,649
Total Accounts Receivable | 7,510 |  | 9,103
Less: Allowance for doubtful accounts | (291) |  | (569)
Total Accounts Receivable, net | 7,219 |  | 8,534
Deferred income | $ | 81 |  | $ | 185
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction | The following table includes estimated revenue expected to be recognized in the future related to performance obligations that are unsatisfied (or partially unsatisfied) at the end of the reporting period:
(in thousands) | 2020 | 2021 | 2022 | 2023 | 2024 | Total
Service and Maintenance | $ | 2,223 | $ | 1,842 | $ | 1,763 | $ | 704 | $ | — | $ | 6,532
Schedule of Inventory | At December 31, 2018 and 2017, inventory consisted of the following (in thousands):
| 2018 |  | 2017
Raw materials - current | $ | 26,152 |  | $ | 22,813
Raw materials - long term | 3,980 |  | 2,829
Finished Goods | 1,022 |  | 1,022
Work in process | 3,800 |  | 2,389
Total | $ | 34,954 |  | $ | 29,053
Summary of Rental Equipment and Property and Equipment | The majority of our property and equipment, including rental equipment, is a direct cost to generating revenue and the following table depicts the depreciation associated with each product line at December 31, 2018 , 2017 and 2015 (in thousands):
| 2018 |  | 2017 |  | 2016
Rentals | $ | 21,588 |  | $ | 20,861 |  | $ | 21,325
Sales | 265 |  | 265 |  | 291
Service & Maintenance | 22 |  | 21 |  | 25
Total | $ | 21,875 |  | $ | 21,147 |  | $ | 21,641
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, 2018 |  |  |  |  |  | December 31, 2017 |  |  |  |
|  | Useful Life (years) |  | Gross Carrying Value |  |  | Accumulated Amortization |  | Net Book Value |  | Gross Carrying Value |  | Accumulated Amortization |  | Net Book Value
Developed Technology |  | 20 |  | $ | 2,505 |  | $ | 1,758 |  | $ | 747 |  | $ | 2,505 |  | $ | 1,633 |  | $ | 872
Trade Name |  | Indefinite |  | 654 |  | — |  | 654 |  | 654 |  | — |  | 654
Total |  |  |  | $ | 3,159 |  | $ | 1,758 |  | $ | 1,401 |  | $ | 3,159 |  | $ | 1,633 |  | $ | 1,526
Schedule of Identified Indefinite-Lived Intangible Assets | The following table represents the identified intangible assets by major asset class (in thousands):
|  |  |  | December 31, 2018 |  |  |  |  |  | December 31, 2017 |  |  |  |
|  | Useful Life (years) |  | Gross Carrying Value |  |  | Accumulated Amortization |  | Net Book Value |  | Gross Carrying Value |  | Accumulated Amortization |  | Net Book Value
Developed Technology |  | 20 |  | $ | 2,505 |  | $ | 1,758 |  | $ | 747 |  | $ | 2,505 |  | $ | 1,633 |  | $ | 872
Trade Name |  | Indefinite |  | 654 |  | — |  | 654 |  | 654 |  | — |  | 654
Total |  |  |  | $ | 3,159 |  | $ | 1,758 |  | $ | 1,401 |  | $ | 3,159 |  | $ | 1,633 |  | $ | 1,526
Computation of Basic and Diluted Earnings Per Share | The following table sets forth the computation of basic and diluted earnings per share (in thousands, except per share amounts):
| Year Ended December 31, |  |  |  |
| 2018 |  | 2017 |  | 2016
Numerator: |  |  |  |  |
Net income | $ | 426 |  | $ | 19,851 |  | $ | 6,469
Denominator for basic net income per common share: |  |  |  |  |
Weighted average common shares outstanding | 12,965 |  | 12,831 |  | 12,702
Denominator for diluted net income per share: |  |  |  |  |
Weighted average common shares outstanding | 12,965 |  | 12,831 |  | 12,702
Dilutive effect of stock options and restricted shares | 268 |  | 279 |  | 233
Diluted weighted average shares | 13,233 |  | 13,110 |  | 12,935
Earnings per common share: |  |  |  |  |
Basic | $ | 0.03 |  | $ | 1.55 |  | $ | 0.51
Diluted | $ | 0.03 |  | $ | 1.51 |  | $ | 0.50

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