Major Customers (Details)	3 Months Ended
	Jul. 31, 2014 Customer	Jul. 31, 2013 Customer
Concentration Risk [Line Items]
Concentration risk, percentage (in hundredths)	10.00%
Revenue [Member] | Customer Concentration Risk [Member] | From Unrelated Customers [Member] | Gaming Business [Member]
Concentration Risk [Line Items]
Number of major customers		1
Concentration risk, percentage (in hundredths)		86.00%
Revenue [Member] | Customer Concentration Risk [Member] | From Unrelated Customers [Member] | Voting Business [Member]
Concentration Risk [Line Items]
Number of major customers	3
Concentration risk, percentage (in hundredths)	85.00%
Revenue [Member] | Customer Concentration Risk [Member] | From Related Customers [Member] | No Individual Customer [Member]
Concentration Risk [Line Items]
Number of major customers	0	0
Concentration risk, percentage (in hundredths)	10.00%	10.00%