XML 69 R54.htm IDEA: XBRL DOCUMENT v3.8.0.1
Investments (Available-for-sale Securities) (Details) - USD ($)
$ in Millions
Sep. 30, 2017
Mar. 31, 2017
Available-for-sale Equity Securities, Amortized Cost Basis [Abstract]    
Cost basis $ 2.6 $ 2.6
Gross unrealized gain 10.2 5.4
Fair value $ 12.8 $ 8.0