Condensed Consolidated Statement of Stockholders' Equity (Unaudited) - 3 months ended Mar. 31, 2017 - USD ($) $ in Thousands	Common Stock [Member] Common Class A [Member]	Common Stock [Member]	Retained Earnings [Member]	Treasury Stock [Member] Common Class A [Member]	Treasury Stock [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2016	8,073,993	71,229,497		(1,669,131)	(5,135,406)
Balance at Dec. 31, 2016	$ 21,764	$ 658,135	$ (101,365)	$ (23,340)	$ (44,688)	$ (17,645)	$ 492,861
Adoption of ASU 2016-09 excess tax benefit for stock-based compensation at Dec. 31, 2016			1,107				1,107
Net income			10,505				10,505
401(k) plan		$ 7					7
401(k) plan (in shares)		557
2007 Long Term Incentive Plan -restricted stock (in shares)	198,220	307,943		(81,561)	(77,632)
2007 Long Term Incentive Plan -restricted stock				$ (892)	$ (874)		(1,766)
Share-based compensation	$ 570	$ 767					1,338
Balance (in shares) at Mar. 31, 2017	8,272,213	71,537,997		(1,750,692)	(5,213,038)
Balance at Mar. 31, 2017	$ 22,334	$ 658,909	$ (89,753)	$ (24,232)	$ (45,562)	$ (17,645)	$ 504,051