Operations and Significant Accounting Policies - Supplemental Statement of Cash Flows Information - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Supplemental Cash Flow Information [Abstract]
Cash Paid for Interest – Net of Amounts Capitalized	$ 24.6	$ 22.4
Income Taxes Paid	0.0	0.3
Noncash Investing and Financing Activities [Abstract]
Decrease in Accounts Payable for Capital Additions to Property, Plant and Equipment	(7.1)	(24.5)
Capitalized Asset Retirement Costs	2.4	3.0
AFUDC–Equity	0.5	0.9
Cash, Cash Equivalents, Restricted Cash and Restricted Cash Equivalents	$ 39.6	$ 75.0

Increase (Decrease) in Accounts Payable for Capital Additions to Property, Plant and Equipment

No definition available.

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- Definition

Amount of cash and cash equivalents, and cash and cash equivalents restricted to withdrawal or usage. Excludes amount for disposal group and discontinued operations. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits. Cash equivalents include, but are not limited to, short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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- References

No definition available.

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- Definition

The amount of cash paid during the current period to foreign, federal, state, and local authorities as taxes on income, net of any cash received during the current period as refunds for the overpayment of taxes.

+ References

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- Definition

The increase (decrease) during the reporting period in the capitalized cost of equity (based on assumed rate of return) and / or borrowed funds (based on interest rate) used to finance construction of regulated assets, which is expected to be recovered through rate adjustments. As a result of this capitalization, net income is increased. This element pertains to certain regulated industries, such as public utilities.

+ References

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- Definition

The increase (decrease) during the reporting period in the carrying amount of asset retirement obligations.

+ References

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- Definition

Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

+ References

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- References

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