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Selected Balance Sheet Information: Changes to Allowance for Credit Losses (Details) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Selected Balance Sheet Information [Abstract] |  |
Balance at Beginning of Year | $ 2.1 | $ 2.2
Additions Charged to Costs and Expenses | 5.8 | 4.0
Recoveries and Other Additions | 2.4 | 2.8
Write-offs and Other Deductions | (8.2) | (7.6)
Balance at End of Year | $ 2.1 | $ 1.4

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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(4)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147479344/326-20-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Publisher FASB -URI https://asc.fasb.org/1943274/2147481962/310-10-50-4 + Details
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- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 13 -Subparagraph (e) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479319/326-20-50-13 + Details
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