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Debt and Credit Facility - Summary of Interest Relating to Senior Notes and Revolving Credit Facility (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Debt Instrument [Line Items] |  |  |  |
Total interest expense | $ 12.1 | $ 12.5 | $ 36.5 | $ 37.2
Senior Notes and Revolving Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest expense capitalized as construction in progress | (0.9) | (0.2) | (2.3) | (0.6)
Total interest expense | 12.1 | 12.5 | 36.5 | 37.2
Revolving Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Revolving Credit Facility commitment fees and finance cost amortization | 0.6 | 0.3 | 1.6 | 1.2
Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes interest expense, including debt issuance cost amortization | $ 12.4 | $ 12.4 | $ 37.2 | $ 36.6

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