Income Taxes and Accounting for Uncertainty in Income Taxes (Details) (USD $)	3 Months Ended	12 Months Ended
	Sep. 30, 2013	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Income Taxes and Accounting for Uncertainty in Income Taxes
NOL for federal income tax purposes		$ 0
NOL benefit for state income tax purposes		24,000,000
Tax benefit related to credit carryforwards		13,000,000
Current (provision) benefit:
Federal		(162,737,000)	28,503,000	(252,741,000)
State		2,421,000	8,730,000	(30,211,000)
Foreign		(13,316,000)
Total from continuing operations		(173,632,000)	37,233,000	(282,952,000)
Deferred (provision) benefit:
Federal		(102,971,000)	(355,220,000)	(572,202,000)
State		(23,223,000)	(47,843,000)	(32,430,000)
Decrease (increase) in valuation allowance			33,839,000	(3,181,000)
Total from continuing operations		(126,194,000)	(369,224,000)	(607,813,000)
Total benefit (provision)		(299,826,000)	(331,991,000)	(890,765,000)
Income (loss) before income taxes		1,136,915,000	994,910,000	2,413,139,000
Portion of Income (loss) before income taxes related to foreign operations			9,000,000
Reconciliation of amounts computed by applying the statutory Federal tax rate to income before taxes
Statutory rate (as a percent)		(35.00%)	(35.00%)	(35.00%)
State income taxes, net of Federal benefit (as a percent)		(1.30%)	(2.60%)	(1.60%)
Reversal of uncertain tax position (as a percent)		9.00%
Other (as a percent)		0.90%	0.80%	(0.60%)
Decrease (increase) in valuation allowance (as a percent)			3.40%	0.30%
Total benefit (provision) for income taxes (as a percent)		(26.40%)	(33.40%)	(36.90%)
Reversal of an uncertain tax position that was resolved		102,000,000
Deferred tax assets:
NOL, credit and other carryforwards		20,947,000	19,737,000
Accrued expenses		53,700,000	68,496,000
Stock-based compensation		23,174,000	27,088,000
Deferred revenue		54,330,000	67,023,000
Total deferred tax assets		152,151,000	182,344,000
Valuation allowance		(9,515,000)	(6,903,000)
Deferred tax asset after valuation allowance		142,636,000	175,441,000
Deferred tax liabilities:
Depreciation and amortization		(1,864,691,000)	(1,711,663,000)
Unrealized gains on investments		(58,435,000)	(11,670,000)
Other liabilities		(35,336,000)	(32,976,000)
Total deferred tax liabilities		(1,958,462,000)	(1,756,309,000)
Net deferred tax asset (liability)		(1,815,826,000)	(1,580,868,000)
Current portion of net deferred tax asset		129,864,000	93,767,000
Noncurrent portion of net deferred tax asset (liability)		(1,945,690,000)	(1,674,635,000)
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Balance as of beginning of period		328,951,000	235,067,000	193,320,000
Additions based on tax positions related to the current year		12,736,000	110,435,000	12,721,000
Additions based on tax positions related to prior years		66,307,000		34,762,000
Reductions based on tax positions related to prior years		(104,796,000)	(5,477,000)	(1,169,000)
Reductions based on tax positions related to settlements with taxing authorities	(102,000,000)	(139,022,000)	(1,739,000)	(1,185,000)
Reductions based on tax positions related to the lapse of the statute of limitations		(12,823,000)	(9,335,000)	(3,382,000)
Balance as of end of period		$ 151,353,000	$ 328,951,000	$ 235,067,000