Fair Value Measurements (Summary Of Fair Values, Principal Balances, And Carrying Values Of Company's Debt Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013 Fair Value [Member]	Dec. 31, 2012 Fair Value [Member]	Dec. 31, 2013 Principal Balance [Member]	Dec. 31, 2012 Principal Balance [Member]	Dec. 31, 2013 Carrying Value [Member]	Dec. 31, 2012 Carrying Value [Member]	Dec. 31, 2013 1.875% Convertible Senior Notes [Member]	Apr. 18, 2013 1.875% Convertible Senior Notes [Member]	May 16, 2008 1.875% Convertible Senior Notes [Member]	Dec. 31, 2012 1.875% Convertible Senior Notes [Member] Fair Value [Member]	Dec. 31, 2012 1.875% Convertible Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2012 1.875% Convertible Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2013 4.0% Convertible Senior Notes [Member]	Apr. 29, 2009 4.0% Convertible Senior Notes [Member]	Dec. 31, 2013 4.0% Convertible Senior Notes [Member] Fair Value [Member]	Dec. 31, 2012 4.0% Convertible Senior Notes [Member] Fair Value [Member]	Dec. 31, 2013 4.0% Convertible Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2012 4.0% Convertible Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2013 4.0% Convertible Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2012 4.0% Convertible Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2013 8.25% Senior Notes [Member]	Jul. 24, 2009 8.25% Senior Notes [Member]	Dec. 31, 2013 8.25% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2012 8.25% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2013 8.25% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2012 8.25% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2013 8.25% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2012 8.25% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2013 5.625% Senior Notes [Member]	Sep. 28, 2012 5.625% Senior Notes [Member]	Dec. 31, 2013 5.625% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2012 5.625% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2013 5.625% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2012 5.625% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2013 5.625% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2012 5.625% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2013 5.75% Senior Notes [Member]	Jul. 13, 2012 5.75% Senior Notes [Member]	Dec. 31, 2013 5.75% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2012 5.75% Senior Notes [Member] Fair Value [Member]	Dec. 31, 2013 5.75% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2012 5.75% Senior Notes [Member] Principal Balance [Member]	Dec. 31, 2013 5.75% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2012 5.75% Senior Notes [Member] Carrying Value [Member]	Dec. 31, 2013 4.254% 2010-1 Tower Securities [Member]	Apr. 16, 2010 4.254% 2010-1 Tower Securities [Member]	Dec. 31, 2013 4.254% 2010-1 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2012 4.254% 2010-1 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 4.254% 2010-1 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2012 4.254% 2010-1 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 4.254% 2010-1 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2012 4.254% 2010-1 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 5.101% 2010-2 Tower Securities [Member]	Apr. 16, 2010 5.101% 2010-2 Tower Securities [Member]	Dec. 31, 2013 5.101% 2010-2 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2012 5.101% 2010-2 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 5.101% 2010-2 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2012 5.101% 2010-2 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 5.101% 2010-2 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2012 5.101% 2010-2 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 2.933% 2012-1 Tower Securities [Member]	Aug. 09, 2012 2.933% 2012-1 Tower Securities [Member]	Dec. 31, 2013 2.933% 2012-1 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2012 2.933% 2012-1 Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 2.933% 2012-1 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2012 2.933% 2012-1 Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 2.933% 2012-1 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2012 2.933% 2012-1 Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 2.240% 2013-1C Tower Securities [Member]	Apr. 18, 2013 2.240% 2013-1C Tower Securities [Member]	Dec. 31, 2013 2.240% 2013-1C Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 2.240% 2013-1C Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 2.240% 2013-1C Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 3.722% 2013-2C Tower Securities [Member]	Apr. 18, 2013 3.722% 2013-2C Tower Securities [Member]	Dec. 31, 2013 3.722% 2013-2C Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 3.722% 2013-2C Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 3.722% 2013-2C Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 3.598% 2013-1D Tower Securities [Member]	Apr. 18, 2013 3.598% 2013-1D Tower Securities [Member]	Dec. 31, 2013 3.598% 2013-1D Tower Securities [Member] Fair Value [Member]	Dec. 31, 2013 3.598% 2013-1D Tower Securities [Member] Principal Balance [Member]	Dec. 31, 2013 3.598% 2013-1D Tower Securities [Member] Carrying Value [Member]	Dec. 31, 2013 Revolving Credit Facility [Member] Fair Value [Member]	Dec. 31, 2012 Revolving Credit Facility [Member] Fair Value [Member]	Dec. 31, 2013 Revolving Credit Facility [Member] Principal Balance [Member]	Dec. 31, 2012 Revolving Credit Facility [Member] Principal Balance [Member]	Dec. 31, 2013 Revolving Credit Facility [Member] Carrying Value [Member]	Dec. 31, 2012 Revolving Credit Facility [Member] Carrying Value [Member]	Dec. 31, 2013 2011 Term Loan B [Member] Fair Value [Member]	Dec. 31, 2012 2011 Term Loan B [Member] Fair Value [Member]	Dec. 31, 2013 2011 Term Loan B [Member] Principal Balance [Member]	Dec. 31, 2012 2011 Term Loan B [Member] Principal Balance [Member]	Dec. 31, 2013 2011 Term Loan B [Member] Carrying Value [Member]	Dec. 31, 2012 2011 Term Loan B [Member] Carrying Value [Member]	Dec. 31, 2013 2012-1 Term Loan A [Member] Fair Value [Member]	Dec. 31, 2012 2012-1 Term Loan A [Member] Fair Value [Member]	Dec. 31, 2013 2012-1 Term Loan A [Member] Principal Balance [Member]	Dec. 31, 2012 2012-1 Term Loan A [Member] Principal Balance [Member]	Dec. 31, 2013 2012-1 Term Loan A [Member] Carrying Value [Member]	Dec. 31, 2012 2012-1 Term Loan A [Member] Carrying Value [Member]	Dec. 31, 2013 2012-2 Term Loan [Member] Fair Value [Member]	Dec. 31, 2012 2012-2 Term Loan [Member] Fair Value [Member]	Dec. 31, 2013 2012-2 Term Loan [Member] Principal Balance [Member]	Dec. 31, 2012 2012-2 Term Loan [Member] Principal Balance [Member]	Dec. 31, 2013 2012-2 Term Loan [Member] Carrying Value [Member]	Dec. 31, 2012 2012-2 Term Loan [Member] Carrying Value [Member]	Dec. 31, 2013 BNDE Loan [Member]	Dec. 31, 2013 BNDE Loan [Member] Fair Value [Member]	Dec. 31, 2013 BNDE Loan [Member] Principal Balance [Member]	Dec. 31, 2013 BNDE Loan [Member] Carrying Value [Member]
Fair Value Inputs Assets Liabilities Quantitative Information [Line Items]
Debt instrument, Fair Value	$ 6,923,448	$ 6,478,465	$ 5,910,041	$ 5,440,073	$ 5,876,607	$ 5,356,103				$ 714,096	$ 468,836	$ 457,351			$ 1,479,859	$ 1,060,622	$ 499,944	$ 499,987	$ 468,394	$ 430,751			$ 262,031	$ 272,391	$ 243,750	$ 243,750	$ 242,387	$ 242,205			$ 514,375	$ 523,750	$ 500,000	$ 500,000	$ 500,000	$ 500,000			$ 832,000	$ 848,000	$ 800,000	$ 800,000	$ 800,000	$ 800,000			$ 689,717	$ 713,619	$ 680,000	$ 680,000	$ 680,000	$ 680,000			$ 586,586	$ 621,379	$ 550,000	$ 550,000	$ 550,000	$ 550,000			$ 604,736	$ 635,614	$ 610,000	$ 610,000	$ 610,000	$ 610,000			$ 408,442	$ 425,000	$ 425,000			$ 530,098	$ 575,000	$ 575,000			$ 318,856	$ 330,000	$ 330,000	$ 215,000	$ 100,000	$ 215,000	$ 100,000	$ 215,000	$ 100,000	$ 180,980	$ 493,731	$ 180,529	$ 492,500	$ 180,234	$ 491,518	$ 184,538	$ 194,513	$ 185,000	$ 195,000	$ 185,000	$ 195,000	$ 110,383	$ 300,750	$ 109,971	$ 300,000	$ 109,745	$ 299,278	$ 5,847	$ 5,847	$ 5,847	$ 5,847
Debt instrument stated percentage							1.875%	1.875%	1.875%				4.00%	4.00%							8.25%	8.25%							5.625%	5.625%							5.75%	5.75%							4.254%	4.254%							5.101%	5.101%							2.933%	2.933%							2.24%	2.24%				3.722%	3.722%				3.598%	3.598%