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Equity (Details Textual) - USD ($)							1 Months Ended			3 Months Ended				6 Months Ended	12 Months Ended	18 Months Ended
Equity (Details Textual) - USD ($)	May 05, 2020	Aug. 01, 2019	May 08, 2019	Feb. 11, 2019	Jun. 12, 2018	Jun. 08, 2018	Apr. 22, 2020	Feb. 29, 2020	Jun. 08, 2018	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2020	Mar. 11, 2013
Equity (Textual)
Remaining number of shares available for repurchase										6,000,000.0				6,000,000.0		6,000,000.0
Dividends on preferred stock										$ 370,000	$ 370,000	$ 370,000	$ 370,000
Dividends declared per common share										$ 0.085	$ 0.075	$ 0.075	$ 0.075
Percentage ownership after all transactions														86.10%
Stock option and incentive plan to reserve			372,000													30,000
Unrecognized compensation cost										$ 3,000,000.0				$ 3,000,000.0		$ 3,000,000.0
Weighted-average period														2 years 7 months 6 days
Treasury stock outstanding														1,200,000	1,000,000.0
Treasury stock cost														$ 9,200,000	$ 7,700,000
Weighted average cost per share														$ 7.42	$ 7.46
Board of Directors [Member]
Equity (Textual)
Deferred stock units vested								$ 305,000
Howard S. Jonas [Member]
Equity (Textual)
Stockholders grant of options purchase				126,176
Exercise price				$ 8.05
Lieu of cash bonus				$ 300,000
Preferred Stock [Member]
Equity (Textual)
Dividends on preferred stock
Stockholders grant of options purchase
Preferred Stock [Member] \| Subsequent Event [Member]
Equity (Textual)
Preferred stock, dividends per share							$ 0.1594
Paid date of declared dividend							Aug. 14, 2020
Record date of declared dividend							Aug. 06, 2020
Class A common stock [Member]
Equity (Textual)
Dividends on preferred stock
Stockholders grant of options purchase
Class A common stock [Member] \| Subsequent Event [Member]
Equity (Textual)
Dividends declared per common share	$ 0.0850
Paid date of declared dividend	Aug. 26, 2020
Record date of declared dividend	Aug. 18, 2020
Class B common stock [Member]
Equity (Textual)
Common stock issued for stock repurchase program														$ 1,500
Number of stock authorized to be repurchased																	7,000,000.0
Dividends on preferred stock
Dividends declared per common share		$ 0.075
Expiration date of the option														Jun. 30, 2023
Paid date of declared dividend		Aug. 23, 2019
Record date of declared dividend		Aug. 16, 2019
Warrants to purchase shares										1,257,862				1,257,862		1,257,862
Warrants exercise price per share										$ 4.77				$ 4.77		$ 4.77
Stockholders grant of options purchase											20		198
Aggregate cost of acquired														$ 1,500,000
Acquired shares										200,873				213,206
Class B common stock [Member] \| Howard S. Jonas [Member]
Equity (Textual)
Expiration date of the option									Jun. 30, 2023
Warrants to purchase shares						1,048,218			1,048,218
Warrants exercise price per share						$ 4.77			$ 4.77
Amount of warrants aggregate exercise price						$ 5,000,000.0
Class B common stock [Member] \| Investor [Member]
Equity (Textual)
Amount of aggregate sales price					$ 1,000,000.0
Warrants to purchase shares					209,644
Warrants exercise price per share					$ 4.77
Amount of warrants aggregate exercise price					$ 1,000,000.0