Consolidated Statements Of Stockholders' Equity (Deficit) - USD ($) $ in Thousands	Total	Accumulated Deficit [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total [Member]	Common Stock Including Additional Paid in Capital
Balance at Dec. 31, 2017		$ (17,694,790)	$ (2,941)	$ (1,260,271)	$ 16,437,460
Stock Issued During Period, Value, Employee Stock Purchase Plan					12,836
Stock Issued During Period, Value, Conversion of Convertible Securities					(159,592)
Net income	$ 582,489	582,489
Impact from adoption of ASU 2014-09		(22,512)
Other Comprehensive Income (Loss), Net of Tax	130		130
Stock-based compensation					54,574
Repurchase of common stock					638,152
Balance at Dec. 31, 2018		(17,089,789)	(2,811)	(1,385,474)	15,707,126
Stock Issued During Period, Value, Employee Stock Purchase Plan					13,152
Stock Issued During Period, Value, Conversion of Convertible Securities					0
Net income	612,299	612,299
Impact from adoption of ASU 2014-09		0
Other Comprehensive Income (Loss), Net of Tax	190		190
Stock-based compensation					52,316
Repurchase of common stock					782,583
Balance at Dec. 31, 2019	(1,490,100)	(16,477,490)	(2,621)	(1,490,100)	14,990,011
Stock Issued During Period, Value, Employee Stock Purchase Plan					12,577
Stock Issued During Period, Value, Conversion of Convertible Securities					0
Net income	814,888	814,888
Impact from adoption of ASU 2014-09		0
Other Comprehensive Income (Loss), Net of Tax	(135)		(135)
Stock-based compensation					50,026
Repurchase of common stock					777,454
Balance at Dec. 31, 2020	$ (1,390,198)	$ (15,662,602)	$ (2,756)	$ (1,390,198)	$ 14,275,160