Fixed Assets (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Depreciation expense	$ 34.3	$ 32.5	$ 28.0
Disposal Group, Held-for-sale, Not Discontinued Operations \| Clearwater, Florida Office Building
Property, Plant and Equipment [Line Items]
Property held for sale	20.2
Gain on sale of land	$ (0.8)

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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- Definition

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

+ References

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

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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.

+ References

No definition available.

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