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Income Taxes (Reconciliation of Statutory Taxes to Effective Taxes) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2018
Income Tax Disclosure [Abstract] |  |  |
Tax at U.S. federal statutory income tax rate of 35% | $ 19.8 | $ 17.2 | $ 23.4
Adjustments to reconcile to income tax expense (benefit): |  |  |
Federal Valuation Allowance | 0.1 | 1.3 | 0.5
State income taxes, net of federal benefit | 3.3 | 3.2 | 4.8
Domestic production activities deduction | 0.0 | 0.0 | (2.4)
Effective Income Tax Rate Reconciliation, Change in Enacted Tax Rate, Amount | 0.0 | 0.0 | (42.5)
Federal transition tax | 0.0 | (0.6) | 7.5
Uncertain tax positions | 1.0 | (1.4) | 0.0
Basis difference in foreign investment | 0.1 | (1.1) | 0.0
Excess tax benefits related to stock compensation | (0.5) | (0.3) | (0.6)
Tax Credits | (1.8) | (1.8) | (1.7)
Other nondeductible expenses | 0.4 | 1.3 | 0.5
Foreign income taxes | 0.0 | 0.1 | 0.0
Nondeductible compensation | 0.6 | 0.3 | 0.2
Other income tax | (0.9) | 0.1 | 0.4
Income tax expense (benefit) | $ 22.1 | $ 18.3 | $ (9.9)

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- Definition Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB TOPIC 6.I.7) -URI http://asc.fasb.org/extlink&oid=116825942&loc=d3e330036-122817 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32672-109319 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22663-107794 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 20 -Section 45 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120385591&loc=d3e38679-109324 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 220 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(9)) -URI http://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=109234566&loc=d3e22658-107794 + Details
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