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Financing: At-the-Market Equity Offering Program (Details) - Common Stock - USD ($) $ / shares in Units, shares in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Proceeds, (net of issuance costs) | $ 31,200,000 | $ 27,400,000
Average price per share | $ 52.51 | $ 62.21
Number of shares issued | 0.6 | 0.4
Payments of Stock Issuance Costs | $ (300,000) | $ (300,000)
August 4, 2020 ATM Program |  |
Proceeds, (net of issuance costs) | $ 0 | $ 27,400,000
Number of shares issued | 0.0 | 0.4
Payments of Stock Issuance Costs | $ 0 | $ (0.3)
June 16, 2023 ATM Program |  |
Proceeds, (net of issuance costs) | $ 31,200,000 | $ 0
Number of shares issued | 0.6 | 0.0
Payments of Stock Issuance Costs | $ (0.3) | $ 0

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- Definition At the market equity offering program average price per share. + References No definition available. + Details
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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 -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-15 + Details
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