Condensed Consolidated Statements of Changes in Stockholders' Equity (Deficit) (USD $) In Thousands, except Share data, unless otherwise specified	Total USD ($)	Par Value USD ($)	Unearned KSOP Contributions USD ($)	Additional Paid-in Capital USD ($)	Treasury Stock USD ($)	Retained Earnings USD ($)	Accumulated Other Comprehensive Losses USD ($)	Class A Common Stock Issued
Balance at Dec. 31, 2012	$ 255,591	$ 137	$ (483)	$ 1,044,746	$ (1,605,376)	$ 905,727	$ (89,160)
Balance, shares at Dec. 31, 2012								544,003,038
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	348,380					348,380
Other comprehensive income	45,672						45,672
Treasury stock acquired	(278,938)				(278,938)
KSOP shares earned	14,930		177	14,753
Stock options exercised	137,759			119,236	18,523
Restricted stock lapsed	991			333	658
Employee stock purchase plan	1,662			1,533	129
Stock based compensation	21,087			21,087
Other stock issuances	455			418	37
Balance at Dec. 31, 2013	547,589	137	(306)	1,202,106	(1,864,967)	1,254,107	(43,488)
Balance, shares at Dec. 31, 2013								544,003,038
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	115,558					115,558
Other comprehensive income	666						666
Treasury stock acquired	(88,728)				(88,728)
KSOP shares earned	3,901		36	3,865
Stock options exercised	15,002			12,749	2,253
Restricted stock lapsed	61			(30)	91
Employee stock purchase plan	494			449	45
Stock based compensation	4,983			4,983
Balance at Mar. 31, 2014	$ 599,526	$ 137	$ (270)	$ 1,224,122	$ (1,951,306)	$ 1,369,665	$ (42,822)
Balance, shares at Mar. 31, 2014								544,003,038