CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Total	Common Class A [Member]	Additional paid-in capital [Member]	Retained earnings [Member]	Treasury stock [Member]	Accumulated other comprehensive loss [Member]
Balance at Dec. 31, 2013	$ 38,730,000	$ 4,038,000	$ 11,798,000	$ 25,871,000	$ (2,977,000)	$ 0
Balance (in shares) at Dec. 31, 2013		4,038,000			(344,000)
Net income	2,080,000	$ 0	0	2,080,000	$ 0	0
Exercise of stock options	745,000	$ 98,000	653,000	0	$ (6,000)	0
Exercise of stock options (in shares)		98,000			(1,000)
Purchase of common stock	(1,583,000)	$ 0	0	0	$ (1,583,000)	0
Purchase of common stock (in shares)		0			(209,000)
Issuance of restricted common stock	27,000	$ 3,000	24,000	0	$ 0	0
Issuance of restricted common stock (in shares)		3,000			0
Stock-based compensation	220,000	$ 0	220,000	0	$ 0	0
Foreign currency translation adjustment	(228,000)	0	0	0	0	(228,000)
Balance at Dec. 31, 2014	39,991,000	$ 4,139,000	12,695,000	27,951,000	$ (4,566,000)	(228,000)
Balance (in shares) at Dec. 31, 2014		4,139,000			(554,000)
Net income	3,544,000	$ 0	0	3,544,000	$ 0	0
Exercise of stock options	73,500	$ 23,500	50,000	0	$ 0	0
Exercise of stock options (in shares)		23,500			0
Issuance of restricted common stock	42,500	$ 7,500	35,000	0	$ 0	0
Issuance of restricted common stock (in shares)		7,500			0
Stock-based compensation	86,000	$ 0	86,000	0	$ 0	0
Tax benefit on stock-based compensation	18,000	0	18,000	0	0	0
Foreign currency translation adjustment	(113,000)	0	0	0	0	(113,000)
Balance at Dec. 31, 2015	$ 43,642,000	$ 4,170,000	$ 12,884,000	$ 31,495,000	$ (4,566,000)	$ (341,000)
Balance (in shares) at Dec. 31, 2015		4,170,000			(554,000)