Contractual interest rate for funds borrowed, under the debt agreement.

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Percentage of principal amount of debt redeemed.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Aggregate amount of interest expense on all borrowings.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

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Debt and Credit Facility - Summary of Senior Notes (Parenthetical) (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	May 31, 2021	Dec. 31, 2021	Dec. 31, 2022
Debt Instrument [Line Items]
Loss on extinguishment of debt		$ (35.9)
Senior Notes
Debt Instrument [Line Items]
Unamortized debt issuance costs		$ 13.7	$ 11.9
4.50% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument contractual rate (percent)		4.50%	4.50%
6.50% Senior Notes
Debt Instrument [Line Items]
Percentage of redemption price of principal amount	108.83%
Debt accrued and unpaid interest	$ 1.3
Repayments of Senior Debt	382.2
Loss on extinguishment of debt	(35.9)
Premium payment	30.9
Unamortized debt issuance costs	$ 5.0
6.50% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument contractual rate (percent)	6.50%	6.50%	6.50%
4.625% Senior Notes \| Senior Notes
Debt Instrument [Line Items]
Debt instrument contractual rate (percent)		4.625%	4.625%