Income Taxes (Details Textual) $ in Millions	3 Months Ended
Jul. 31, 2017 USD ($)
Income Taxes (Textual) [Abstract]
Time period over which it is reasonably possible that the Company could increase or decrease its unrecognized tax benefits	12 months
Amount unrecognized tax benefit could decrease in next 12 months	$ 6.7

The amount of the unrecognized tax benefit of a position taken for which it is reasonably possible that the total amount thereof will significantly increase or decrease within twelve months of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=65882285&loc=d3e32718-109319

Name:	us-gaap_SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant