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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		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Debt Instrument [Line Items]
Total interest expense	$ 11.4	$ 12.1	$ 35.4	$ 36.5
Senior Notes and Revolving Credit Facility
Debt Instrument [Line Items]
Interest expense capitalized as construction in progress	(1.8)	(0.9)	(4.7)	(2.3)
Total interest expense	11.4	12.1	35.4	36.5
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving Credit Facility, including commitment fees and finance cost amortization	0.8	0.6	2.9	1.6
Senior Notes
Debt Instrument [Line Items]
Senior Notes. including debt issuance cost amortization	$ 12.4	$ 12.4	$ 37.2	$ 37.2

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