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The Company - U.S. Department of Energy Carbon Free Power Project Award (Details) - Carbon Free Power Project Award (Award 8369) - USD ($) $ in Thousands | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2019 | Apr. 30, 2015 | Dec. 31, 2021
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Cost share | $ 8,250 | $ 16,617 |
Cost share (as a percent) | 50.00% | 50.00% |
Maximum amount awarded | $ 126,694 |  |
Cumulative cash received |  |  | $ 7,451
Amount paid to third party for services provided |  |  | $ 729
Reimburse percentage |  |  | 25.00%
Maximum reimbursement amount |  |  | $ 4,100
Accounts Receivable [Member] |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Amount obligated under current budget period |  |  | $ 70
Government [Member] |  |  |
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items] |  |  |
Cost share | $ 8,250 | $ 16,617 |
Cost share (as a percent) | 50.00% | 50.00% |

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