Income Taxes and Accounting for Uncertainty in Income Taxes (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Income Taxes and Accounting for Uncertainty in Income Taxes
NOL for federal income tax purposes	$ 2,000
NOL benefit for state income tax purposes	127,000
Tax benefit related to credit carryforwards	71,000
Current (benefit) provision:
Federal	(230,935)	$ 173,326	$ 44,451
State	22,566	43,579	29,918
Foreign	7,471	6,203	4,616
Total current (benefit) provision	(200,898)	223,108	78,985
Deferred (benefit) provision:
Federal	610,528	204,403	383,096
State	243,216	21,732	64,000
Increase (decrease) in valuation allowance	45,429	2,115	7,603
Total deferred (benefit) provision	899,173	228,250	454,699
Total (benefit) provision	698,275	451,358	533,684
Income (loss) before income taxes	2,572,211	$ 1,943,927	$ 2,189,175
Portion of Income (loss) before income taxes related to foreign operations	$ 18,000
Reconciliation of amounts computed by applying the statutory Federal tax rate to income before taxes
Statutory rate (as a percent)	21.00%	21.00%	21.00%
State income taxes, net of Federal benefits (as a percent)	4.60%	3.20%	4.60%
State apportionment changes (as a percent)	5.40%
Cares Act NOL Carryback (as a percent)	(2.30%)
Other, net (as a percent)	(1.60%)	(1.00%)	(1.20%)
Total (benefit) provision for income taxes (as a percent)	27.10%	23.20%	24.40%
Deferred tax assets:
NOL, credit and other carryforwards	$ 128,968	$ 368,545
Accrued expenses		8,488
Stock-based compensation	17,962	19,821
Unrealized (gains) losses on available for sale and other investments	9,862	4,137
Deferred revenue	26,977	17,238
Total deferred tax assets	183,769	418,229
Valuation allowance	(73,788)	(28,359)
Deferred tax asset after valuation allowance	109,981	389,870
Deferred tax liabilities:
Depreciation	(467,922)	(583,374)
Accrued and prepaid expenses	(72,314)
FCC authorizations and other intangible amortization	(2,542,887)	(2,040,885)
Bases difference in partnerships and cost method investments (1)	(744,911)	(573,548)
Discount on convertible notes and convertible note hedge transaction, net	(151,517)	(62,718)
Total deferred tax liabilities	(3,979,551)	(3,260,525)
Net deferred tax asset (liability)	(3,869,570)	(2,870,655)
Reconciliation of the beginning and ending amount of unrecognized tax benefits
Balance as of beginning of period	674,207	385,394	$ 393,916
Additions based on tax positions related to the current year	233	244,257	10,350
Additions based on tax positions related to prior years	1,999	61,909	1,670
Reductions based on tax positions related to prior years	(296,265)	(13,028)	(6,291)
Reductions based on tax positions related to settlements with taxing authorities	(831)	(2,362)	(8,328)
Reductions based on tax positions related to the lapse of the statute of limitations	(876)	(1,963)	(5,923)
Balance as of end of period	$ 378,467	674,207	$ 385,394
Additional uncertain tax benefits		$ 274,000