Available borrowing capacity.

No definition available.

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- Definition

Commercial Paper, Maximum Borrowing Capacity

+ References

No definition available.

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- Definition

Number Of One-Year Extension Options

+ References

No definition available.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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- Definition

Amount, before accumulated amortization, of debt issuance costs classified as noncurrent. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 835
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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

The effective interest rate at the end of the reporting period.

+ References

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- Definition

Maximum amount borrowed under the credit facility at any time during the period.

+ References

No definition available.

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ Details

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- Definition

Amount of cash inflow from short-term debt classified as other.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Amount of cash outflow for the payment of debt classified as other, maturing within one year or the operating cycle, if longer.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Reference 1: http://www.xbrl.org/2003/role/exampleRef
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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.

+ References

No definition available.

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Financing: Short-Term Debt: (Details) $ in Millions	12 Months Ended
Financing: Short-Term Debt: (Details) $ in Millions	Dec. 31, 2023 USD ($) CreditExtension	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Short-term Debt [Line Items]
Amount outstanding	$ 0.0	$ 535.6
Commercial Paper, Maximum Borrowing Capacity	750.0
Term Loan - borrowings	0.0	0.0	$ 800.0
Repayments of Other Short-term Debt	$ 0.0	0.0	$ 800.0
Commercial Paper
Short-term Debt [Line Items]
Debt Instrument, Term	397 days
Revolving Credit Facility
Short-term Debt [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 750.0
Number Of One-Year Extension Options \| CreditExtension	2
Debt Instrument, Term	1 year
Maximum amount outstanding (based on daily outstanding balances)	$ 1,000.0
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.175%
Debt Issuance Cost, Gross, Noncurrent	$ 8.9
Revolving Credit Facility \| Base Rate
Short-term Debt [Line Items]
Weighted average interest rates	0.125%
Revolving Credit Facility \| Eurodollar
Short-term Debt [Line Items]
Weighted average interest rates	1.125%
Revolving Credit Facility \| Letter of Credit
Short-term Debt [Line Items]
Weighted average interest rates	1.125%
Revolving Credit Facility \| Commercial Paper
Short-term Debt [Line Items]
Amount outstanding	$ 0.0	535.6
Letters of credit	3.7	24.6
Available capacity	746.3	$ 189.8
Weighted average interest rates		4.88%
Maximum amount outstanding (based on daily outstanding balances)	548.7	$ 572.3
Average amount outstanding (based on daily outstanding balances)	$ 81.7	$ 390.7
Weighted average interest rates	4.91%	2.11%