Income Taxes (Reconciliation of U.S. Federal Statutory Tax Rate) (Details) |
12 Months Ended | ||
|---|---|---|---|
May 31, 2017 |
May 31, 2016 |
May 31, 2015 |
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| Income Taxes [Abstract] | |||
| Federal statutory tax rate | 35.00% | 35.00% | 35.00% |
| State income taxes, net of federal tax benefit | 2.80% | 3.00% | 3.00% |
| Section 199 - Qualified production activities | (0.50%) | (2.40%) | |
| Tax-exempt municipal bond interest | (1.30%) | (1.40%) | (1.50%) |
| Stock option windfall benefit | (1.50%) | ||
| Other items | (0.20%) | 0.10% | (0.20%) |
| Effective income tax rate | 34.30% | 34.30% | 36.30% |
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- Definition Effective Income Tax Rate Reconciliation Stock Option Windfall Benefit No definition available.
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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage 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 deduction for qualified production activity. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage 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 other adjustments. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage 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 applicable to state and local income tax expense (benefit), net of federal tax expense (benefit). Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Percentage 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 income (loss) exempt from income taxes. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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