Debt and Credit Arrangements - (Schedule of Debt) (Details) - USD ($) $ in Millions |
Mar. 31, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Short-term: | ||
| Short-term debt | $ 50.1 | $ 375.0 |
| Long-term: | ||
| Long-term debt principal | 800.0 | 850.1 |
| Unamortized debt issuance costs | (6.3) | (6.8) |
| Total long-term debt | 793.7 | 843.3 |
| Total debt | 843.8 | 1,218.3 |
| Senior debentures maturing April 15, 2026 [Member] | ||
| Short-term: | ||
| Short-term debt | 0.0 | 375.0 |
| Senior debentures maturing September 1, 2035 [Member] | ||
| Long-term: | ||
| Long-term debt principal | 500.0 | 500.0 |
| Senior debentures maturing September 1, 2030 [Member] | ||
| Long-term: | ||
| Long-term debt principal | 300.0 | 300.0 |
| Subordinated debentures maturing February 3, 2027 [Member] | ||
| Short-term: | ||
| Short-term debt | 50.1 | 0.0 |
| Long-term: | ||
| Long-term debt principal | $ 0.0 | $ 50.1 |
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- Definition Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount, after accumulated amortization, of debt discount. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Represents the aggregate of total long-term debt, including current maturities and short-term debt. No definition available.
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- Definition Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- References No definition available.
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