Consolidated Statements Of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2012	$ 7,441	$ 4,472	$ 295,643	$ 53	$ (17,038)	$ 290,571
Balance, shares at Dec. 31, 2012	6,894,000
Net earnings			41,252			41,252
Unrealized loss on available-for-sale securities				(45)		(45)
Other		526			247	773
Other, shares	8,000
Balance at Dec. 31, 2013	$ 7,441	4,998	336,895	8	(16,791)	332,551
Balance, shares at Dec. 31, 2013	6,902,000
Net earnings			26,477			26,477
Unrealized loss on available-for-sale securities				(11)		(11)
Dividends paid			(34,954)			(34,954)
Other		908	(1)		473	1,380
Other, shares	15,000
Balance at Dec. 31, 2014	$ 7,441	5,906	328,417	(3)	(16,318)	$ 325,443
Balance, shares at Dec. 31, 2014	6,917,000					6,917,222
Net earnings			40,496			$ 40,496
Unrealized loss on available-for-sale securities				(6)		(6)
Dividends paid			(28,114)			(28,114)
Other		869			566	1,435
Other, shares	18,000
Balance at Dec. 31, 2015	$ 7,441	$ 6,775	$ 340,799	$ (9)	$ (15,752)	$ 339,254
Balance, shares at Dec. 31, 2015	6,935,000					6,935,471