Condensed Consolidated Statement of Stockholders' Equity (Unaudited) - 9 months ended Sep. 30, 2017 - USD ($) $ in Thousands	Common Stock [Member] Common Class A [Member]	Common Stock [Member] Common Class B [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2016	$ 170	$ 24	$ 137,912	$ (1,084)	$ (2,640)	$ 102,032	$ 236,414
Net income						6,141	6,141
Other comprehensive income					1,198		1,198
Stock-based employee compensation expense			646				646
Issuance of restricted shares			(1,091)	1,084			(7)
Balance at Sep. 30, 2017	$ 170	$ 24	$ 137,467		$ (1,442)	$ 108,173	$ 244,392