Consolidated Statements of Shareholders' Equity (USD $) In Thousands	Common Class A [Member] Common Stock [Member]	Common Class A [Member]	Common Class B [Member] Common Stock [Member]	Common Class B [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Balances at December 31, 2011 at Dec. 31, 2011	$ 24		$ 4		$ 31,060	$ 46,995	$ 907	$ (23,436)	$ 55,554
Purchase of treasury stock								(5,168)	(5,168)
Issuance of common shares for the excercise of stock options	1				5,967				5,968
Tax benefit from the exercise of options and vested restricted stock					2,078				2,078
Non-cash stock compensation expense					388				388
Dividends declared per common share						(17,363)			(17,363)
Other comprehensive (loss), foreign currency translation adjustment							217		217
Net income		7,534		7,534		15,068			15,068
Balances at Dec. 31, 2012	25		4		39,493	44,700	1,124	(28,604)	56,742
Purchase of treasury stock								(206)	(206)
Issuance of common shares for the excercise of stock options					990				990
Tax benefit from the exercise of options and vested restricted stock					755				755
Non-cash stock compensation expense					955				955
Fractional share cashed out					(1)				(1)
Dividends declared per common share						(2,142)			(2,142)
Other comprehensive (loss), foreign currency translation adjustment							(822)		(822)
Net income		7,741		7,743		15,484			15,484
Balances at Dec. 31, 2013	25		4		42,192	58,042	302	(28,810)	71,755
Purchase of treasury stock								(1,248)	(1,248)
Issuance of common shares for the excercise of stock options					1,308				1,308
Tax benefit from the exercise of options and vested restricted stock					622				622
Non-cash stock compensation expense					742				742
Dividends declared per common share						(2,512)			(2,512)
Other comprehensive (loss), foreign currency translation adjustment							(1,075)		(1,075)
Net income		9,062		9,094		18,156			18,156
Balances at Dec. 31, 2014	$ 25		$ 4		$ 44,864	$ 73,686	$ (773)	$ (30,058)	$ 87,748