Recently Issued Accounting Standards Recently Issued Accounting Standards (Details) - USD ($) $ in Millions	Oct. 31, 2019	May 01, 2019	Apr. 30, 2019
Operating lease right-of-use assets	$ 153.2		$ 0.0
Total operating lease liabilities	160.6
Accounting Standards Update 2016-02 [Member]
Operating lease right-of-use assets		$ 159.2
Total operating lease liabilities		$ 166.6
New Accounting Pronouncement, Early Adoption, Effect [Member] | Accounting Standards Update 2018-15 [Member] | Other Noncurrent Assets [Member]
Capitalized third-party cloud computing implementation costs	$ 2.4