Quarterly report pursuant to Section 13 or 15(d)

Goodwill and Intangible Assets, Net of Accumulated Amortization (Narrative) (Details)

v3.8.0.1
Goodwill and Intangible Assets, Net of Accumulated Amortization (Narrative) (Details) - USD ($)
$ in Millions
3 Months Ended 9 Months Ended
Feb. 28, 2018
Feb. 28, 2017
Feb. 28, 2018
Feb. 28, 2017
May 31, 2017
Goodwill and Intangible Assets, Net of Accumulated Amortization [Abstract]          
Goodwill $ 827.4   $ 827.4   $ 657.1
Increased in goodwill result of HROI acquisition     170.3    
Amortization expense $ 5.1 $ 4.6 $ 14.3 $ 13.5