Schedule of Nonvested Performance-based Units Activity (Details) (USD $)	9 Months Ended
	Jan. 31, 2015
Common Stock Schedule Of Nonvested Performance-based Units Activity 1	$ 1,937,918
Common Stock Schedule Of Nonvested Performance-based Units Activity 2	0.87
Common Stock Schedule Of Nonvested Performance-based Units Activity 3	871,000
Common Stock Schedule Of Nonvested Performance-based Units Activity 4	0.49
Common Stock Schedule Of Nonvested Performance-based Units Activity 5	(622,293)
Common Stock Schedule Of Nonvested Performance-based Units Activity 6	0.87
Common Stock Schedule Of Nonvested Performance-based Units Activity 7	(342,917)
Common Stock Schedule Of Nonvested Performance-based Units Activity 8	0.68
Common Stock Schedule Of Nonvested Performance-based Units Activity 9	$ 1,843,708
Common Stock Schedule Of Nonvested Performance-based Units Activity 10	0.72