Equity (Details Textual) - USD ($)		1 Months Ended	3 Months Ended
	Dec. 01, 2015	Sep. 24, 2015	Oct. 31, 2015	Oct. 31, 2014
Equity (Textual)
Dividends paid			$ 4,200,000	$ 4,000,000
Dividends declared, per share			$ 0.18	$ 0.85
Class A common stock
Equity (Textual)
Dividends paid per share in cash			0.18	0.17
Class A common stock | Board of Directors [Member]
Equity (Textual)
Dividends declared, per share				0.68
Class A common stock | Subsequent Event [Member]
Equity (Textual)
Common stock dividends declared	$ 0.19
Paid date of declared dividend	Dec. 18, 2015
Record date of declared dividend	Dec. 14, 2015
Class B common stock
Equity (Textual)
Dividends paid per share in cash			$ 0.18	$ 0.17
Stock repurchase program, remaining number of shares authorized to be repurchased			5,000,000
Restricted Class B common stock purchased from employees, Shares			8,300,000
Aggregate purchase price of shares repurchased				$ 400,000
Class B common stock shares repurchased				29,675
Class B common stock | Board of Directors [Member]
Equity (Textual)
Number of options granted		100,000
Dividends declared, per share				$ 0.68
Class B common stock | Employees
Equity (Textual)
Aggregate purchase price of shares repurchased			$ 23,000	$ 100,000
Class B common stock shares repurchased			1,542	8,637
Class B common stock | Subsequent Event [Member]
Equity (Textual)
Common stock dividends declared	$ 0.19
Paid date of declared dividend	Dec. 18, 2015
Record date of declared dividend	Dec. 14, 2015