Share-Based Payments (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Restricted Stock Units (RSUs) [Member]
Total unrecognized compensation cost related to unvested RSU awards	$ 10.6
Weighted average remaining expense life	1 year 7 months 6 days
Total intrinsic value of shares vested	$ 23.3	$ 18.1	$ 17.2
Dividend Equivalent Units [Member]
Total intrinsic value of shares vested	$ 0.9	0.7	0.6
Cash Incentive Plan [Member]
Weighted average remaining expense life	9 months 18 days
Share Based Compensation Liability Awards Amount Of Liability	$ 10.5	11.1
Cash incentive unit payments made	$ 3.0	$ 2.9	$ 2.2

The liability recorded in connection with our Cash Incentive Plan.

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- Definition

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (i)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

Amount of cash paid to settle liability for award under share-based payment arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (d)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480429/718-10-50-2

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

+ References

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