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Fair Value - Recurring Fair Value Measures (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Liabilities:
Aggregate amount of available-for-sale corporate and governmental debt securities maturing in one year or less	$ 2.0
Aggregate amount of available-for-sale corporate and governmental debt securities maturing in one year to less than three years	2.8
Aggregate amount of available-for-sale corporate and governmental debt securities maturing in three years to less than five years	1.5
Aggregate amount of available-for-sale corporate and governmental debt securities maturing in five years or more	0.5
Recurring Fair Value Measures
Investments
Available-for-sale – Equity Securities	8.6	$ 8.7
Available-for-sale – Corporate and Governmental Debt Securities	6.8	6.0
Cash Equivalents	8.5	5.8
Total Fair Value of Assets	23.9	20.5
Liabilities:
Deferred Compensation	21.1	16.5
Total Fair Value of Liabilities	21.1	16.5
Recurring Fair Value Measures | Level 1
Investments
Available-for-sale – Equity Securities	8.6	8.7
Available-for-sale – Corporate and Governmental Debt Securities	0.0	0.0
Cash Equivalents	8.5	5.8
Total Fair Value of Assets	17.1	14.5
Liabilities:
Deferred Compensation	0.0	0.0
Total Fair Value of Liabilities	0.0	0.0
Recurring Fair Value Measures | Level 2
Investments
Available-for-sale – Equity Securities	0.0	0.0
Available-for-sale – Corporate and Governmental Debt Securities	6.8	6.0
Cash Equivalents	0.0	0.0
Total Fair Value of Assets	6.8	6.0
Liabilities:
Deferred Compensation	21.1	16.5
Total Fair Value of Liabilities	21.1	16.5
Recurring Fair Value Measures | Level 3
Investments
Available-for-sale – Equity Securities	0.0	0.0
Available-for-sale – Corporate and Governmental Debt Securities	0.0	0.0
Cash Equivalents	0.0	0.0
Total Fair Value of Assets	0.0	0.0
Liabilities:
Deferred Compensation	0.0	0.0
Total Fair Value of Liabilities	$ 0.0	$ 0.0

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Amount of available-for-sale debt securities at fair value maturing in after the fifth fiscal year following the latest fiscal year (maturing in five years or more).

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Amount of available-for-sale debt securities at fair value maturing after the first fiscal year through the third fiscal year following the latest fiscal year (maturing in more than one year to less than three years).

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Amount of available-for-sale debt securities at fair value maturing after the third fiscal year through the fifth fiscal year following the latest fiscal year (maturing in three years to less than five years).

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Fair value portion of asset recognized for present right to economic benefit.

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), classified as noncurrent.

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Fair value of financial and nonfinancial obligations.

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Amount of noncurrent assets that are pledged or subject to withdrawal restrictions, classified as other.

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