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SUPPLEMENTAL CASH FLOW INFORMATION (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Supplemental cash flow information: |  |  |
Cash paid for interest | $ 2,096 | $ 1,204 | $ 3,089
Cash payments related to income taxes, net | 18,860 | 4,172 | 255
Supplemental non-cash investing and financing activities: |  |  |
Property, plant and equipment acquired with equipment notes | 0 | 9,407 | 1,216
Property, plant and equipment purchased but not yet paid | 34,569 | 14,082 | 4,054
SNR Mineral Rights Acquisition | 0 | 0 | 324,125
Revenue recognized in exchange for debt principal reduction | 13,566 | 54,802 | 21,312
Paycheck Protection Loan forgiveness | 0 | 3,401 | 0
Decrease in estimates of asset retirement costs | 10,395 | 8,713 | 0
Operating right-of-use assets obtained in exchange for lease liabilities | 168 | 0 | 2,932
Finance right-of-use assets obtained in exchange for lease liabilities | $ 42 | $ 88 | $ 724

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- Definition Future cash outflow to pay for purchases of fixed assets that have occurred. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 5 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4332-108586 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 4 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4313-108586 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 3 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4304-108586 + Details
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- Definition The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 50 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126999549&loc=d3e4297-108586 + Details
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