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, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Debt Instrument [Line Items]
Total interest expense	$ 11.1	$ 12.1	$ 22.6	$ 24.0
Senior Notes and Revolving Credit Facility
Debt Instrument [Line Items]
Interest expense on finance lease liabilities	0.2	0.2	0.4	0.3
Interest expense capitalized as construction in progress	(2.1)	(1.5)	(3.8)	(2.9)
Total interest expense	11.1	12.1	22.6	24.0
Revolving Credit Facility
Debt Instrument [Line Items]
Revolving Credit Facility interest expense, including commitment fees and finance cost amortization	0.6	1.0	1.2	1.8
Senior Notes
Debt Instrument [Line Items]
Senior Notes interest expense, including debt issuance cost amortization	$ 12.4	$ 12.4	$ 24.8	$ 24.8