Stock-Based Compensation (Schedule of Share-Based Payment Arrangement, Expensed and Capitalized, Amount) (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Employee Stock Option
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
Share-Based Payment Arrangement, Expense	$ 0.8	$ 1.1	$ 3.0	$ 3.2
Share-Based Payment Arrangement, Expense, Tax Benefit	0.2	0.3	0.8	0.9
Share-Based Payment Arrangement, Amount Capitalized	0.4	0.5	1.4	1.6
Other Equity Awards [Member]
Share-Based Payment Arrangement, Additional Disclosure [Abstract]
Share-Based Payment Arrangement, Expense	9.6	9.3	29.3	27.1
Share-Based Payment Arrangement, Expense, Tax Benefit	2.4	2.4	7.4	7.0
Share-Based Payment Arrangement, Amount Capitalized	$ 4.6	$ 4.2	$ 13.7	$ 11.8

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479830/718-10-S99-1

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

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Amount of cost capitalized 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 (h)(1)(ii)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Amount of tax benefit for recognition of expense of 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 (h)(1)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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