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Income Taxes Income Tax Rate Reconciliation (Details) | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Sep. 30, 2017
Effective Income Tax Rate Reconciliation, Percent [Abstract] |  |  |  |  |
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent | 21.00% | 24.50% | 21.00% | 24.50% | 35.00%
Adjustments to reconcile to the effective tax rate: |  |  |  |  |
State income taxes, net of federal benefit | 4.50% | 4.80% | 5.60% | 4.50% |
Tax benefits from stock compensation | (0.30%) | (0.20%) | (1.40%) | (1.20%) |
U.S. manufacturing deduction | 0.00% | (1.70%) | 0.00% | (1.60%) |
Tax credits | (1.20%) | (1.10%) | (2.70%) | (1.00%) |
Effective Income Tax Rate Reconciliation, GILTI, percent | 0.60% | 0.00% | 1.20% | 0.00% |
FIN 48 statute release | (5.20%) | 0.00% | (7.20%) | 0.00% |
Other | 1.90% | 1.90% | 3.60% | (0.20%) |
Walter Energy accrual | (0.40%) | 0.00% | 4.60% | 0.00% |
Effective Income Tax Rate Reconciliation, Transition Tax | 0.00% | 0.00% | (1.90%) | 12.30% |
Change in rate for deferred taxes | 0.00% | 0.00% | 0.00% | (69.80%) |
Effective income tax rate | 20.90% | 28.20% | 22.70% | (32.10%) |

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