Debt and Other Financing (Schedule of Public Notes) (Details) - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
5.00% Notes, due March 2023
Debt Instrument [Line Items]
Remaining Principal	$ 0.0	$ 461.9
Unamortized Discounts	0.0	(0.5)
Unamortized Debt Issuance Costs	0.0	(0.6)
Total	0.0	460.8
6.95% Notes, due March 2043
Debt Instrument [Line Items]
Remaining Principal	216.1	216.1
Unamortized Discounts	(1.6)	(1.7)
Unamortized Debt Issuance Costs	(0.5)	(0.5)
Total	$ 214.0	$ 213.9

Amount, after accumulated amortization, of debt discount.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI https://asc.fasb.org/extlink&oid=124435984&loc=d3e28541-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI https://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant