Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended		4 Months Ended	6 Months Ended		8 Months Ended	12 Months Ended
	Oct. 31, 2018	Oct. 31, 2017	Apr. 30, 2018	Oct. 31, 2018	Oct. 31, 2017	Dec. 31, 2017	Apr. 30, 2018
Income Tax Disclosure [Abstract]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	35.00%	21.00%	21.00%	35.00%	35.00%
Net impact of discrete adjustments							$ (765.8)
Effective Income Tax Rate Reconciliation, Percent	30.00%	33.30%		27.30%	33.20%
Income Taxes (Textual) [Abstract]
Time Period Over Which it is Reasonably Possible That Company Could Increase or Decrease its Unrecognized Tax Benefits				12 months
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	$ 9.7			$ 9.7