Other noncurrent assets - Components (Details) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Other assets:
Note receivables - OPA	$ 114.2	$ 91.6
Pension asset	22.0	19.8
Operating lease right-of-use assets	21.0	20.6
IBNR receivables	15.1	15.0
Land held for development	6.2	7.4
Restricted cash and cash equivalents	6.1	5.5
Other	17.2	21.4
Total	$ 201.8	$ 181.3

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Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans.

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Amortized cost, before allowance for credit loss, of financing receivable classified as noncurrent. Excludes net investment in lease.

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Amount of lessee's right to use underlying asset under operating lease.

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Amount of other miscellaneous assets expected to be realized or consumed after one year or normal operating cycle, if longer.

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Amount of noncurrent assets classified as other.

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Estimated amount after valuation allowance of reinsurance recoverables, due from reinsurers for incurred claims not yet reported, and claims settlement expenses.

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Amount of cash and cash equivalent restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposit with financial institution, and account with general characteristic of demand deposit. Cash equivalent includes, but is not limited to, short-term, highly liquid investment that is both readily convertible to known amount of cash and so near maturity that it presents insignificant risk of change in value because of change in interest rate.

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Land held for development noncurrent.

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