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Financing: At-the-Market Equity Offering Program (Details) - USD ($) $ / shares in Units, $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Number of shares issued | 436,202 | 216,885 | 881,780 | 272,592
August 4, 2020 ATM Program |  |  |  |
Number of shares issued | 329,647 | 216,885 | 775,225 | 272,592
June 16, 2023 ATM Program |  |  |  |
Number of shares issued | 106,555 |  | 106,555 |
Common Stock |  |  |  |
Proceeds, (net of issuance costs) | $ 27.4 | $ 16.4 | $ 54.9 | $ 20.2
Average price per share | $ 63.53 | $ 76.39 | $ 62.86 | $ 74.84
Payments of Stock Issuance Costs | $ (0.3) | $ (0.2) | $ (0.6) | $ (0.2)
Common Stock | August 4, 2020 ATM Program |  |  |  |
Proceeds, (net of issuance costs) | 21.0 | 16.4 | 48.5 | 20.2
Payments of Stock Issuance Costs | (0.2) | (0.2) | (0.5) | (0.2)
Common Stock | June 16, 2023 ATM Program |  |  |  |
Proceeds, (net of issuance costs) | 6.4 |  | 6.4 |
Payments of Stock Issuance Costs | $ (0.1) | $ 0.0 | $ (0.1) | $ 0.0

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- Definition The cash outflow for cost incurred directly with the issuance of an equity security. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3291-108585 + Details
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