Stock Based Compensation (RSU Activity) (Details) - Long-Term Equity Incentive Plan - Restricted Stock Units - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Compensation expense	$ 34.9	$ 32.8	$ 29.4
Income tax benefit	(6.4)	(5.9)	(5.2)
Share-based compensation expense, net of tax	$ 28.5	$ 26.9	$ 24.2

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI https://asc.fasb.org/extlink&oid=128089324&loc=d3e5070-113901

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