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- Definition

Cash-backed bank guarantee facilities

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Cash Collateral, Percentage of the aggregate amount of letters of credit outstanding

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Cash Collateral, Percentage of the aggregate amount of letters of credit outstanding if credit rating falls below threshold

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Cash-collateralized Letters of Credit

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Debt outstanding deemed to be funded

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Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Discussion of whether the debt instrument is secured or unsecured, and, if secured, a description of the collateral and guarantees required or provided.

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

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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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Amount of interest expense classified as operating and nonoperating. Includes, but is not limited to, cost of borrowing accounted for as interest expense.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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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.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Financial Instruments and Other Guarantees - Narratives (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
	Jan. 18, 2024	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Nov. 03, 2025	Dec. 31, 2024	Feb. 13, 2023
Guarantee Obligations [Line Items]
Interest expense, net of capitalized interest		$ 10.0	$ 9.7	$ 32.6	$ 35.1
Restricted Cash		717.8		717.8			$ 682.2
Cash-backed bank guarantee facilities		205.9		205.9
Capitalized debt issuance costs related to ARS amendment		1.8
Letter of Credit
Guarantee Obligations [Line Items]
Line of Credit Facility, Commitment Fee Percentage	0.50%
Line of credit facility, maximum borrowing capacity		$ 250.0		$ 250.0
Cash Collateral, Percentage of the aggregate amount of letters of credit outstanding		103.00%		103.00%
Stated interest rate		0.75%		0.75%
Collateralized Letter of Credit Agreement
Guarantee Obligations [Line Items]
Cash-collateralized Letters of Credit		$ 119.1		$ 119.1
Letter of credit amendment \| Subsequent Event
Guarantee Obligations [Line Items]
Cash Collateral, Percentage of the aggregate amount of letters of credit outstanding						102.00%
Cash Collateral, minimum						103.00%
Surety Trust Account
Guarantee Obligations [Line Items]
Restricted Cash		392.8		$ 392.8			$ 394.6
Accounts Receivable Securitization Program
Guarantee Obligations [Line Items]
Line of credit facility, maximum borrowing capacity								$ 225.0
Accounts Receivable Securitization Program \| Secured debt
Guarantee Obligations [Line Items]
Basis spread on variable rate				2.10%
Maximum
Guarantee Obligations [Line Items]
Basis spread on variable rate	3.25%
Maximum \| Letter of Credit
Guarantee Obligations [Line Items]
Basis spread on variable rate	4.25%
Transaction support agreements, additional collateral demands		5.0		$ 5.0
Minimum
Guarantee Obligations [Line Items]
Basis spread on variable rate	2.50%
Minimum \| Letter of Credit
Guarantee Obligations [Line Items]
Basis spread on variable rate	3.50%
Surety Bond
Guarantee Obligations [Line Items]
Surety Agreement Liquidity Covenant, Amount		400.0		400.0
Difference between penal sum of all surety bonds and amount of collateral posted in favor of surety providers		493.9		493.9
Collateral amount held in trust account		392.8		392.8
Collateral amount held in letters of credit		$ 126.4		$ 126.4
Surety Bond \| Maximum
Guarantee Obligations [Line Items]
Net Leverage Ratio		1.5		1.5
Debt Instrument, Collateral		519.2 million
Surety Bond \| Minimum
Guarantee Obligations [Line Items]
Net Leverage Ratio		1.0		1.0
Senior Notes \| 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)
Guarantee Obligations [Line Items]
Debt Instrument, Funded, Percent		50.00%		50.00%
Stated interest rate		3.25%		3.25%
Secured debt \| Accounts Receivable Securitization Program
Guarantee Obligations [Line Items]
Outstanding borrowings		$ 0.0		$ 0.0
Accounts Receivable from Securitization		77.2		77.2
Interest expense, net of capitalized interest		$ 0.6	$ 0.5	$ 1.8	$ 1.9