CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Class A [Member]	Class B [Member]	Additional Paid In Capital [Member]	Accumulated Other Comprehensive Income [Member]	Retained Earnings [Member]	Treasury Stock [Member]
Begining Balance At at Dec. 31, 2008	$ 603,694	$ 969	$ 0	$ 661,703	$ 2,106	$ 282,284	$ (343,368)
Shares Begining Balance At at Dec. 31, 2008		69,396,000	0				(12,679,000)
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Abstract
Net Income (Loss)	75,951	0	0	0	0	75,951	0
Net Unrealized Gain Or Loss On Available For Sale Securities	(2,814)	0	0	0	(2,814)	0	0
Foreign Currency Translation Adjustment	(11)	0	0	0	(11)	0	0
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest	73,126
Adjustment For Adoption Of FSP FAS 115-2 (a)	0	0	0	0	(3,095)	3,095	0
Share Based Compensation	13,556	0	0	13,556	0	0	0
Dividends Declared	(9,488)	0	0	0	0	(9,488)	0
Restricted Stock Value Issued For Deferred Compensation	0	0	0	0	0	0	0
Restricted Stock Issued For Deferred Compensation		202,000	0				0
Restricted Shares Held In Lieu Of Employee Taxes Value	(883)	0	0	0	0	0	(883)
Restricted Shares Held In Lieu Of Employee Taxes Shares		0	0				(70,000)
Excercise Of Stock Options Value	16,123	16	0	16,107	0	0	0
Excercise Of Stock Options Shares		1,134,000	0				0
Tax Effect Of Stock Options Exercised	(869)	0	0	(869)	0	0	0
Ending Balance At at Dec. 31, 2009	695,259	985	0	690,497	(3,814)	351,842	(344,251)
Shares Ending Balance At at Dec. 31, 2009		70,732,000	0				(12,749,000)
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Abstract
Net Income (Loss)	123,335	0	0	0	0	123,335	0
Net Unrealized Gain Or Loss On Available For Sale Securities	1,414	0	0	0	1,414	0	0
Foreign Currency Translation Adjustment	251	0	0	0	251	0	0
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest	125,000
Share Based Compensation	9,669	0	0	9,669	0	0	0
Dividends Declared	(14,461)	0	0	0	0	(14,461)	0
Restricted Stock Value Issued For Deferred Compensation	0	0	0	0	0	0	0
Restricted Stock Issued For Deferred Compensation		401,000	0				0
Restricted Shares Held In Lieu Of Employee Taxes Value	(3,440)	0	0	0	0	0	(3,440)
Restricted Shares Held In Lieu Of Employee Taxes Shares		0	0				(149,000)
Excercise Of Stock Options Value	16,322	10	0	16,312	0	0	0
Excercise Of Stock Options Shares		730,000	0				0
Tax Effect Of Stock Options Exercised	(827)	0	0	(827)	0	0	0
Ending Balance At at Dec. 31, 2010	827,522	995	0	715,651	(2,149)	460,716	(347,691)
Shares Ending Balance At at Dec. 31, 2010		71,863,000	0				(12,898,000)
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest Abstract
Net Income (Loss)	126,540	0	0	0	0	126,540	0
Other Comprehensive Income Defined Benefit Plan Net Prior Service Cost Credit Arising During Period Before Tax	33,771	0	0	0	(33,771)	0	0
Deferred Income Taxes on Establishment of Prior Service Costs on SERP	11,550	0	0	0	11,550	0	0
Amortization of Prior Service Costs - SERP	2,367	0	0	0	2,367	0	0
Net Unrealized Gain Or Loss On Available For Sale Securities	649	0	0	0	649	0	0
Foreign Currency Translation Adjustment	39	0	0	0	39	0	0
Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest	107,374
Share Based Compensation	12,952	0	0	12,952	0	0	0
Dividends Declared	(19,675)	0	0	0	0	(19,675)	0
Restricted Stock Value Issued For Deferred Compensation	0	0	0	0	0	0	0
Restricted Stock Issued For Deferred Compensation		488,000	0				0
Restricted Shares Held In Lieu Of Employee Taxes Value	(5,079)	0	0	0	0	0	(5,079)
Restricted Shares Held In Lieu Of Employee Taxes Shares		0	0				(170,000)
Excercise Of Stock Options Value	58,213	29	0	58,184	0	0	0
Excercise Of Stock Options Shares		2,092,000	0				0
Net Settlement Exercise Of Stock Options Value	0	4	0	7,966	0	0	(7,970)
Net Settlement Exercise of Options, Shares Held in Lieu of Employee Taxes, Value	(1,464)	0	0	0	0	0	(1,464)
Net Settlement Exercise Of Stock Options Shares		297,000	0				(202,000)
Net Settlement Exercise of Options, Shares Held in Lieu of Employee Taxes, Shares		0	0				(37,000)
Treasury Stock Value Acquired Cost Method	(150,086)	0	0	0	0	0	(150,086)
Treasury Stock Shares Acquired		0	0				(4,438,000)
Tax Effect Of Stock Options Exercised	2,226	0	0	2,226	0	0	0
Ending Balance At at Dec. 31, 2011	$ 831,983	$ 1,028	$ 0	$ 796,979	$ (21,315)	$ 567,581	$ (512,290)
Shares Ending Balance At at Dec. 31, 2011		74,740,000	0				(17,745,000)