Quarterly report pursuant to Section 13 or 15(d)

Accumulated Other Comprehensive Income/(Loss) (Changes in Accumulated Other Comprehensive Income/(Loss)) (Details)

v3.19.3
Accumulated Other Comprehensive Income/(Loss) (Changes in Accumulated Other Comprehensive Income/(Loss)) (Details) - USD ($)
$ in Millions
3 Months Ended
Aug. 31, 2019
Aug. 31, 2018
Accumulated Other Comprehensive Income/(Loss) [Abstract]    
Beginning balance $ 0.1 $ (36.2)
Unrealized gains on available-for-sale securities, net of tax 26.1 2.2
Reclassification adjustment for the gain on sale of available-for-sale securities realized in net income, net of tax (0.7) (0.1)
Foreign currency translation adjustment 1.0 (1.7)
Total other comprehensive income, net of tax 26.4 0.4
Ending balance 26.5 (35.8)
Total tax expense included in other comprehensive income $ 8.3 $ 0.5