Annual report pursuant to Section 13 and 15(d)

Income Taxes (Narrative) (Details)

v3.10.0.1
Income Taxes (Narrative) (Details) - USD ($)
$ / shares in Units, $ in Millions
 1 Months Ended 5 Months Ended 12 Months Ended
May 31, 2018
Dec. 31, 2016
May 31, 2018
May 31, 2018
May 31, 2017
May 31, 2016
Income Tax Contingency [Line Items]            
Net operating loss ("NOL") carry forward $ 5.9   $ 5.9 $ 5.9 $ 2.9  
Corporate income tax rate       29.20% 35.00% 35.00%
Blended statutory tax rate       29.20%    
Estimated tax benefits from Tax Act       $ 102.6    
Net tax benefit related to revaluation of net deferred tax liabilities       25.5    
Net tax benefit related to change in annual effective tax rate       $ 77.1    
Diluted earnings per share related to revaluation of net deferred tax liabilities       $ 0.07    
Diluted earnings per share related to change in annual effective tax rate       $ 0.21    
Reserve for uncertain tax positions 14.7   14.7 $ 14.7 $ 39.2  
Income tax expense., current       343.2 410.1 $ 387.2
Impact of uncertain tax positions, if recognized, on effective income tax rate 14.7   $ 14.7 14.7 $ 39.2  
Scenario, Plan [Member]            
Income Tax Contingency [Line Items]            
Corporate income tax rate     21.00%      
Fiscal 2012 Through Fiscal 2014 [Member]            
Income Tax Contingency [Line Items]            
Decreased reserve for uncertain tax positions   $ 28.9        
Fiscal 2012 Through Fiscal 2017 [Member]            
Income Tax Contingency [Line Items]            
Decreased reserve for uncertain tax positions 27.2          
Income tax expense., current 2.7          
Federal [Member]            
Income Tax Contingency [Line Items]            
Net operating loss ("NOL") carry forward 4.1   $ 4.1 $ 4.1    
Federal [Member] | Minimum [Member]            
Income Tax Contingency [Line Items]            
NOL carry forwards, Expiration date       May 31, 2020    
Federal [Member] | Maximum [Member]            
Income Tax Contingency [Line Items]            
NOL carry forwards, Expiration date       May 31, 2035    
State [Member]            
Income Tax Contingency [Line Items]            
Net operating loss ("NOL") carry forward $ 1.8   $ 1.8 $ 1.8    
State [Member] | Minimum [Member]            
Income Tax Contingency [Line Items]            
NOL carry forwards, Expiration date       May 31, 2019    
State [Member] | Maximum [Member]            
Income Tax Contingency [Line Items]            
NOL carry forwards, Expiration date       May 31, 2038