CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Common Class A [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Treasury stock [Member]	Accumulated other comprehensive loss [Member]	Total
Balance at Dec. 31, 2018	$ 4,410,000	$ 13,904,000	$ 34,588,000	$ (6,695,000)	$ (672,000)	$ 45,535,000
Balance (in shares) at Dec. 31, 2018	4,410,000			(816,000)
Net loss	$ 0	0	(26,000)	$ 0	0	(26,000)
Restricted common stock compensation	0	13,000	0	0	0	13,000
Purchase of Class A common stock	$ 0	0	0	$ (3,202,000)	0	(3,202,000)
Purchase of Class A common stock (in shares)	0			(418,000)
Stock-based compensation	$ 0	29,000	0	$ 0	0	29,000
Dividends	0	0	(158,000)	0	0	(158,000)
Foreign currency translation adjustment	0	0	0	0	44,000	44,000
Balance at Mar. 31, 2019	$ 4,410,000	13,946,000	34,404,000	$ (9,897,000)	(628,000)	42,235,000
Balance (in shares) at Mar. 31, 2019	4,410,000			(1,234,000)
Balance at Dec. 31, 2019	$ 4,416,000	14,056,000	38,867,000	$ (10,213,000)	(620,000)	46,506,000
Balance (in shares) at Dec. 31, 2019	4,416,000			(1,273,000)
Net loss	$ 0	0	(758,000)	$ 0	0	(758,000)
Exercise of stock options	$ 1,000	2,000	0	$ 0	0	3,000
Exercise of stock options (in shares)	1,000			0
Restricted common stock compensation	$ 0	13,000	0	$ 0	0	13,000
Stock-based compensation	0	16,000	0	0	0	16,000
Dividends	0	0	(157,000)	0	0	(157,000)
Foreign currency translation adjustment	0	0	0	0	(125,000)	(125,000)
Balance at Mar. 31, 2020	$ 4,417,000	$ 14,087,000	$ 37,952,000	$ (10,213,000)	$ (745,000)	$ 45,498,000
Balance (in shares) at Mar. 31, 2020	4,417,000			(1,273,000)