Income Taxes (Components of Provision for Income Taxes) (Details) - USD ($) $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
May 31, 2017 |
Feb. 28, 2017 |
Nov. 30, 2016 |
Aug. 31, 2016 |
May 31, 2016 |
Feb. 29, 2016 |
Nov. 30, 2015 |
Aug. 31, 2015 |
May 31, 2017 |
May 31, 2016 |
May 31, 2015 |
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| Income Taxes [Abstract] | |||||||||||
| Federal | $ 362.0 | $ 336.4 | $ 341.4 | ||||||||
| State | 48.1 | 50.8 | 47.8 | ||||||||
| Total current | 410.1 | 387.2 | 389.2 | ||||||||
| Federal | 15.9 | 5.5 | (5.1) | ||||||||
| State | 1.5 | 1.6 | 1.0 | ||||||||
| Total deferred | 17.4 | 7.1 | (4.1) | ||||||||
| Income taxes | $ 105.2 | $ 105.3 | $ 109.9 | $ 107.1 | $ 98.0 | $ 101.3 | $ 106.6 | $ 88.4 | $ 427.5 | $ 394.3 | $ 385.1 |
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- Definition Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of current income tax expense (benefit) pertaining to taxable income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of current state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred federal income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred income tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount of deferred state and local tax expense (benefit) pertaining to income (loss) from continuing operations. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- References No definition available.
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- Definition Amount 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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