v3.20.4

Commitments (Tables) | 12 Months Ended
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Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract] |
Schedule of minimum required payments for unconditional purchase obligations | The minimum required payments for unconditional purchase obligations, including the natural gas purchases outlined below, are as follows:
(in thousands) |  |  | Unconditional Purchase Obligations
Year Ending December 31, |  |  |
2021 |  |  | $ | 36,132 |
2022 |  |  | 11,207 |
2023 |  |  | 9,540 |
2024 |  |  | 5,006 |
2025 |  |  | 5,006 |
Thereafter |  |  | 33,244 |
|  |  | $ | 100,135 |

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- Definition Tabular disclosure of unconditional purchase obligation not recognized as liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 440 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121559207&loc=d3e25336-109308 + Details
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