Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Income Statement [Abstract]
Revenues	$ 6,148,286	$ 4,923,116	$ 11,915,977	$ 9,444,108
Cost of revenues	3,643,707	3,005,657	7,243,408	5,876,271
Marketing	434,370	603,150	938,200	1,219,728
Technology and development	435,045	383,233	888,862	755,997
General and administrative	277,236	224,657	529,323	426,609
Operating income	1,357,928	706,419	2,316,184	1,165,503
Other income (expense):
Interest expense	(189,151)	(152,033)	(373,234)	(287,562)
Interest and other income (expense)	(133,175)	(53,470)	(111,478)	22,634
Income before income taxes	1,035,602	500,916	1,831,472	900,575
Provision for income taxes	315,406	230,266	402,209	285,873
Net income	$ 720,196	$ 270,650	$ 1,429,263	$ 614,702
Earnings per share:
Basic (in dollars per share)	$ 1.63	$ 0.62	$ 3.25	$ 1.41
Diluted (in dollars per share)	$ 1.59	$ 0.60	$ 3.15	$ 1.36
Weighted-average common shares outstanding:
Basic (in shares)	440,569	437,587	439,961	437,271
Diluted (in shares)	453,945	452,195	453,220	452,063