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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