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Debt and Credit Facility - Summary of Interest Expense Relating to Senior Notes and Revolving Credit Facility (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2023 | Jun. 30, 2022 | Jun. 30, 2023 | Jun. 30, 2022
Debt Instrument [Line Items] |  |  |  |
Total interest expense | $ 12.1 | $ 12.2 | $ 24.0 | $ 24.4
Senior Notes and Revolving Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Interest expense capitalized as construction in progress | (1.5) | (0.8) | (2.9) | (1.4)
Total interest expense | 12.1 | 12.2 | 24.0 | 24.4
Revolving Credit Facility |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Revolving Credit Facility, including commitment fees and finance cost amortization | 1.2 | 0.6 | 2.1 | 1.0
Senior Notes |  |  |  |
Debt Instrument [Line Items] |  |  |  |
Senior Notes. including debt issuance cost amortization | $ 12.4 | $ 12.4 | $ 24.8 | $ 24.8

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