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Equity (Details Textual) - USD ($) $ / shares in Units, $ in Thousands |  |  | 1 Months Ended | 9 Months Ended |
--- | --- | --- | --- | --- | ---
Nov. 05, 2018 | Jun. 12, 2018 | Oct. 25, 2018 | Aug. 31, 2018 | Jun. 30, 2018 | Jun. 08, 2018 | May 07, 2018 | Aug. 31, 2017 | Sep. 30, 2018 | Sep. 30, 2017 | Mar. 11, 2013
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Remaining number of shares available for repurchase |  |  |  |  |  |  |  |  | 6,900,000 |  |
Dividends on preferred stock |  |  |  |  |  |  |  |  | $ 1,111 | $ 1,111 |
Unrecognized compensation cost |  |  |  |  |  |  |  |  | $ 2,700 |  |
Common stock dividends declared |  |  |  |  |  |  |  |  | $ 0.225 | $ 0.225 |
Weighted-average period |  |  |  |  |  |  |  |  | 2 years |  |
Rothschild [Member] | GOGAS [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Purchases of equity of subsidiary interest |  |  |  |  | 5.00% |  |  |  |  |  |
Fair value of common stock |  |  |  |  | $ 220 |  |  |  |  |  |
Number of common stock shares issued |  |  |  |  | 41,667 |  |  |  |  |  |
Percentage ownership before all transactions |  |  |  |  | 92.00% |  |  |  |  |  |
Percentage ownership after all transactions |  |  |  |  | 97.00% |  |  |  |  |  |
Preferred Stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Preferred stock, dividends per share |  |  | $ 0.1594 |  |  |  |  |  |  |  |
Paid date of declared dividend |  |  | Nov. 15, 2018 |  |  |  |  |  |  |  |
Record date of declared dividend |  |  | Nov. 06, 2018 |  |  |  |  |  |  |  |
Class A common stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Dividends declared per common share | $ 0.075 |  |  |  |  |  |  |  |  |  |
Paid date of declared dividend | Nov. 30, 2018 |  |  |  |  |  |  |  |  |  |
Record date of declared dividend | Nov. 19, 2018 |  |  |  |  |  |  |  |  |  |
Class B common stock [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Number of stock authorized to be repurchased |  |  |  |  |  |  |  |  |  |  | 7,000,000
Warrants expiry term |  |  |  |  |  |  |  |  | Jun. 30, 2023 |  |
Fair value of common stock |  |  |  | $ 1,900 |  |  |  | $ 1,800 |  |  |
Number of common stock shares issued |  |  |  | 310,467 |  |  |  | 287,233 |  |  |
Warrants to purchase shares |  |  |  |  |  |  |  |  | 1,257,862 |  |
Warrants exercise price per share |  |  |  |  |  |  |  |  | $ 4.77 |  |
Aggregate cost of acquired |  |  |  | $ 800 |  |  |  | $ 800 |  |  |
Acquired shares |  |  |  | 128,865 |  |  |  | 129,898 |  |  |
Class B common stock [Member] | Stock-Based Compensation [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Stock option and incentive plan to reserve |  |  |  |  |  |  | 974,199 |  |  |  |
Class B common stock [Member] | Stock-Based Compensation [Member] | Michael M. Stein [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Restricted shares granted |  |  |  |  |  |  | 157,344 |  |  |  |
Fair value of restricted shares grant |  |  |  |  |  |  | $ 900 |  |  |  |
Class B common stock [Member] | Howard S. Jonas [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Warrants expiry term |  |  |  |  |  | Jun. 30, 2023 |  |  |  |  |
Sale of shares |  |  |  |  |  | 1,152,074 |  |  |  |  |
Sale of shares price per share |  |  |  |  |  | $ 4.34 |  |  |  |  |
Amount of aggregate sales price |  |  |  |  |  | $ 5,000 |  |  |  |  |
Warrants to purchase shares |  |  |  |  |  | 1,048,218 |  |  |  |  |
Warrants exercise price per share |  |  |  |  |  | $ 4.77 |  |  |  |  |
Amount of warrants aggregate exercise price |  |  |  |  |  | $ 5,000 |  |  |  |  |
Class B common stock [Member] | Howard S. Jonas [Member] | Stock-Based Compensation [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Stockholders grant of options purchase |  |  |  |  |  |  | 256,818 |  |  |  |
Exercise price |  |  |  |  |  |  | $ 4.34 |  |  |  |
Lieu of cash bonus |  |  |  |  |  |  | $ 300 |  |  |  |
Class B common stock [Member] | Investor [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Sale of shares |  | 230,415 |  |  |  |  |  |  |  |  |
Sale of shares price per share |  | $ 4.34 |  |  |  |  |  |  |  |  |
Amount of aggregate sales price |  | $ 1,000 |  |  |  |  |  |  |  |  |
Warrants to purchase shares |  | 209,644 |  |  |  |  |  |  |  |  |
Warrants exercise price per share |  | $ 4.77 |  |  |  |  |  |  |  |  |
Amount of warrants aggregate exercise price |  | $ 1,000 |  |  |  |  |  |  |  |  |
Class B common stock [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |
Equity (Textual) |  |  |  |  |  |  |  |  |  |  |
Dividends declared per common share | $ 0.075 |  |  |  |  |  |  |  |  |  |
Paid date of declared dividend | Nov. 30, 2018 |  |  |  |  |  |  |  |  |  |
Record date of declared dividend | Nov. 19, 2018 |  |  |  |  |  |  |  |  |  |

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