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Income Taxes (Narrative) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Sep. 30, 2023
Income Tax Disclosure [Abstract] |  |  |  |  |
Unrecognized Tax Benefits | $ 4.1 |  | $ 4.1 |  | $ 5.0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 21.00% | 21.00% | 21.00% |
State income taxes, net of federal benefit | 3.50% | 3.20% | 3.50% | 3.20% |
Tax credits | (1.80%) | (3.50%) | (1.80%) | (2.80%) |
Other | 0.90% | 0.20% | 0.90% | 1.30% |
Other Expense |  |  |  |  |
Income Tax Disclosure [Abstract] |  |  |  |  |
Unrecognized Tax Benefits, Income Tax Indemnification Asset, Expense | $ 0.0 |  | $ 1.6 |  |
Income Tax Information [Line Items] |  |  |  |  |
Unrecognized Tax Benefits, Income Tax Indemnification Asset, Expense | $ 0.0 |  | $ 1.6 |  |

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + 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/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.1.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 + Details
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- Definition Percentage of reported income tax benefit (expense) from difference to income tax expense (benefit) computed by applying statutory federal (national) income tax rate to pretax income (loss) from continuing operation, attributable to other reconciling items. Excludes state and local income tax expense (benefit), federal tax expense (benefit), statutory income tax expense (benefit) outside of country of domicile, tax credit, nondeductible expense, deduction, income tax settlement, income tax contingency, and cross-border tax law. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Subparagraph (b)(3) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 + Details
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