| Dec 31, 2016 | Dec 31, 2017 | Dec 31, 2018 | Dec 31, 2019 | Dec 31, 2020 | Dec 31, 2021 | Dec 31, 2022 | Dec 31, 2023 | Dec 31, 2024 |
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| Cash and cash equivalents | - | 35 | 1 | 3 | 12 | 26 | 6 | 6 | 2 |
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| Accounts receivable | 5 | 23 | 19 | 60 | 70 | 17 | 36 | 23 | 41 |
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| Unbilled receivables | 0 | 1 | 8 | 5 | 0 | 2 | 0 | 3 | 5 |
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| Inventory | 10 | 9 | 19 | 21 | 19 | 15 | 20 | 27 | 25 |
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| Prepaid expenses and other current assets | 1 | 4 | 3 | 2 | 11 | 14 | 7 | 3 | 3 |
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| Total current assets | 65 | 73 | 50 | 90 | 112 | 74 | 68 | 62 | 76 |
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| Property, plant and equipment, net | 104 | 172 | 248 | 230 | 275 | 262 | 259 | 255 | 237 |
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| Operating lease right-of-use assets | - | - | - | 28 | 32 | 30 | 26 | 23 | 23 |
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| Intangible assets, net | - | - | 18 | 9 | 8 | 7 | 7 | 6 | 5 |
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| Other assets | 0 | 1 | 3 | 4 | 1 | 0 | 0 | 0 | 1 |
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| Total assets | 173 | 247 | 320 | 362 | 428 | 374 | 360 | 346 | 342 |
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| Accounts payable | 2 | 26 | 11 | 4 | 3 | 8 | 14 | 16 | 17 |
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| Total accrued liabilities | - | - | - | - | - | 14 | 13 | 11 | 13 |
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| Deferred revenue | - | - | 4 | 8 | 7 | 10 | 7 | 1 | 0 |
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| Current portion of long-term debt | - | - | 1 | 6 | 7 | 7 | 6 | 16 | 4 |
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| Operating Lease, Liability, Current | - | - | - | 13 | 7 | 9 | 11 | 11 | 10 |
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| Total current liabilities | 14 | 35 | 25 | 40 | 37 | 49 | 52 | 54 | 43 |
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| Long-term debt | - | - | 48 | 28 | 22 | 15 | 10 | 3 | 9 |
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| Long-term operating lease liabilities | - | - | - | 15 | 27 | 24 | 18 | 14 | 14 |
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| Deferred tax liabilities, net | - | - | 18 | 24 | 33 | 22 | 18 | 12 | 9 |
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| Asset retirement obligation | 1 | 9 | 13 | 6 | 15 | 16 | 19 | 20 | 21 |
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| Other non-current liabilities | - | - | - | - | 1 | 0 | 0 | 0 | 0 |
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| Total liabilities | 31 | 57 | 111 | 117 | 139 | 133 | 117 | 104 | 98 |
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| Common Stock, Value, Issued | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
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| Treasury stock, at cost, 7,577,759 and 7,371,260 shares at December 31, 2024 and 2023, respectively | - | - | - | - | - | - | - | 14 | 15 |
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| Additional paid-in capital | 133 | 159 | 162 | 165 | 171 | 174 | 178 | 182 | 185 |
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| Retained earnings | 10 | 32 | 50 | 82 | 121 | 71 | 70 | 75 | 73 |
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| Accumulated other comprehensive loss | - | - | -0 | -0 | 0 | 1 | 0 | -0 | -0 |
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| Total stockholders’ equity | 142 | 190 | 209 | 244 | 289 | 241 | 243 | 242 | 244 |
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| Total liabilities and stockholders’ equity | 173 | 247 | 320 | 362 | 428 | 374 | 360 | 346 | 342 |
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