Debt and Credit Facility (4.50% Senior Notes) - Additional Information (Details) - 4.50% Senior Notes - Senior Notes - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	May 31, 2021
Debt Instrument
Debt instrument contractual rate (percent)	4.50%	4.50%
Debt issuance, percentage of principal amount		100.00%
Debt principal amount		$ 550.0
Unamortized debt issuance costs	$ 8.1
Interest expense	$ 15.7
Effective interest rate (percent)	4.70%
Debt instrument, payment terms	Interest accrues on the 4.50% Senior Notes beginning May 20, 2021 at a rate of 4.50% per annum and is payable semiannually on June 1 and December 1 of each year. The first interest payment date was December 1, 2021
Debt instrument, frequency of interest payment	semiannually
Debt Instrument, first interest payment date	Dec. 01, 2021
Fair value of outstanding debt	$ 542.6
Change in control
Debt Instrument
Redemption price as percentage of principal (percent)	101.00%
On or After June 1, 2026
Debt Instrument
Redemption price as percentage of principal (percent)	102.25%
On or After June 1, 2027
Debt Instrument
Redemption price as percentage of principal (percent)	101.50%
On or After June 1, 2028
Debt Instrument
Redemption price as percentage of principal (percent)	100.75%
On or After June 1, 2029
Debt Instrument
Redemption price as percentage of principal (percent)	100.00%
Prior to June 1, 2026
Debt Instrument
Redemption price as percentage of principal (percent)	104.50%
Prior to June 1, 2026 \| Maximum
Debt Instrument
Percentage of principal that can be redeemed (percent)	40.00%
Prior to June1, 2026 Plus Applicable Premium
Debt Instrument
Redemption price as percentage of principal (percent)	100.00%
Upon receipt of the proceeds of certain asset sale
Debt Instrument
Redemption price as percentage of principal (percent)	100.00%

Debt Instrument, Redemption Price, Percentage Of Principal Amount That Can be Redeemed

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- Definition

Debt issuance, percentage of principal amount

+ References

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- Definition

Date the debt agreement requires the first payment to be made, in YYYY-MM-DD format.

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- Definition

Face (par) amount of debt instrument at time of issuance.

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- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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- Definition

Description of the frequency of periodic payments (monthly, quarterly, annual).

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- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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- Definition

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

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Description of the payment terms of the debt instrument (for example, whether periodic payments include principal and frequency of payments) and discussion about any contingencies associated with the payment.

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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Aggregate amount of interest paid or due on all long-term debt.

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- Definition

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.

+ References

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