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Equity (Details) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  | 1 Months Ended | 12 Months Ended |
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Jun. 09, 2017 | Apr. 11, 2017 | Apr. 10, 2017 | Mar. 02, 2017 | Sep. 30, 2017 | May 31, 2016 | Jun. 25, 2015 | Jun. 23, 2015 | Jan. 31, 2015 | Nov. 30, 2014 | Jul. 31, 2017 | Jul. 31, 2016 | Jul. 31, 2015 | May 01, 2017
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Voting rights description |  |  |  |  |  |  |  |  |  |  | The holders of Class A common stock are entitled to three votes per share and the holders of Class B common stock are entitled to one-tenth of a vote per share. |  |  |
Dividends paid per share in cash |  |  |  |  |  |  |  |  | $ 0.64 | $ 0.68 |  |  |  |
Class B common stock aggregate consideration |  |  |  |  |  |  |  |  |  |  | $ 24,930 |  |  |
Proceeds from sale of member interests in CS Pharma Holdings, LLC |  |  |  |  |  |  |  |  |  |  | 10,000 |  |  |
Howard S. Jonas [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of member interests in CS Pharma Holdings, LLC |  |  |  | $ 1,000 |  |  |  |  |  |  |  |  |  |
Class A common stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends paid |  |  |  |  |  |  |  |  |  |  | $ 17,900 | $ 17,400 | $ 47,600 |
Dividends paid per share in cash |  |  |  |  |  |  |  |  |  |  | $ 0.76 | $ 0.75 | $ 2.03 |
Class A common stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends declared |  |  |  |  | $ 0.19 |  |  |  |  |  |  |  |  |
Paid date of declared dividend |  |  |  |  | Oct. 20, 2017 |  |  |  |  |  |  |  |  |
Record date of declared dividend |  |  |  |  | Oct. 16, 2017 |  |  |  |  |  |  |  |  |
Class B Common Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends paid |  |  |  |  |  |  |  |  |  |  | $ 17,490 | $ 17,400 | $ 47,600 |
Dividends paid per share in cash |  |  |  |  |  |  |  |  |  |  | $ 0.76 | $ 0.75 | $ 2.03 |
Restricted Class B common stock purchased from employees, shares |  |  |  |  |  |  |  |  |  |  | 8,000,000 |  |  |
Class B common stock shares repurchased |  |  |  |  |  |  |  |  |  |  |  | 398,376 | 29,675 |
Aggregate purchase price of shares repurchased |  |  |  |  |  |  |  |  |  |  |  | $ 4,600 | $ 400 |
Stock repurchase program, remaining number of shares authorized to be repurchased |  |  |  |  |  |  |  |  |  |  | 8,000,000 |  |  |
Class B Common Stock [Member] | Employee [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Class B common stock shares repurchased |  |  |  |  |  |  |  |  |  |  | 94,338 | 11,250 | 152,856 |
Aggregate purchase price of shares repurchased |  |  |  |  |  |  |  |  |  |  | $ 1,800 | $ 100 | $ 2,800 |
Class B Common Stock [Member] | Howard S. Jonas [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Treasury shares of common stock sold |  | 728,332 |  |  |  |  |  |  |  |  |  |  |  |
Closing price of Class B common stock |  |  | $ 13.73 |  |  |  |  |  |  |  |  |  |  |
Options exercise price |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 14.93
Stock issued for stock option exercises | 1,000,000 |  |  |  |  |  |  |  |  |  |  |  |  |
Purchase price per share |  |  |  |  |  |  |  | $ 18.52 |  |  |  |  |  |
Class B common stock shares repurchased |  |  |  |  |  |  | 404,967 |  |  |  |  |  |  |
Aggregate purchase price of shares repurchased |  |  |  |  |  |  | $ 7,500 |  |  |  |  |  |  |
Aggregate consideration |  | $ 10,000 |  |  |  |  |  |  |  |  |  |  |  |
Class B Common Stock [Member] | Zedge Spin-Off [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of capital stock |  |  |  |  |  | 10.00% |  |  |  |  |  |  |  |
Proceeds from sale of interest in corporate unit intercompany amount paid |  |  |  |  |  | $ 2,600 |  |  |  |  |  |  |  |
Proceeds from sale of interest in corporate unit total received |  |  |  |  |  | $ 3,000 |  |  |  |  |  |  |  |
Class B Common Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common stock dividends declared |  |  |  |  | $ 0.19 |  |  |  |  |  |  |  |  |
Paid date of declared dividend |  |  |  |  | Oct. 20, 2017 |  |  |  |  |  |  |  |  |
Record date of declared dividend |  |  |  |  | Oct. 16, 2017 |  |  |  |  |  |  |  |  |

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