Treasury Stock and Repurchase Program (Detail Textuals) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended		1 Months Ended
	Oct. 31, 2013	Jul. 31, 2013	Oct. 31, 2013	Oct. 31, 2012	Sep. 19, 2012 September 2012 Share Repurchase Program	Jan. 31, 2011 January 2011 Share Repurchase Program	Jan. 31, 2011 Former Repurchase Program
Equity, Class of Treasury Stock [Line Items]
Authorized repurchase amount of common stock					$ 3,000,000
Number of treasury shares	13,428	25,723			19,953	18,400	85,219
Total average cost	$ 123	$ 226	$ 349	$ 30	$ 182,000	$ 354,000	$ 1,036,000