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Income Tax Matters - Reconciliation of Income Tax (Provision) Benefit based on Effective Income Tax Rate and Statutory Tax Rate (Parenthetical) (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Reconciliation between income tax provision and statutory income tax provision: |  |  |
Increase (decrease) in federal valuation allowances | $ 0.0 | $ (1.1) | $ (0.2)
State and Local Jurisdiction |  |  |
Reconciliation between income tax provision and statutory income tax provision: |  |  |
Increase (decrease) in federal valuation allowances | (1.0) | 0.1 | 1.6
State and tax expense (benefit) before adjustments | 1.4 | (1.1) | (0.7)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount | $ (1.9) | $ 1.5 | $ 1.3

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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 + Details
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- Definition Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to increase (decrease) in the income tax rates. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482685/740-10-50-12 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 15 -Publisher FASB -URI https://asc.fasb.org//1943274/2147482525/740-10-45-15 + Details
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