Selected Quarterly Financial Data (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2020	Sep. 30, 2020	Jun. 30, 2020	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Quarterly Financial Information Disclosure [Abstract]
Total revenues	$ 6,644,442	$ 6,435,637	$ 6,148,286	$ 5,767,691	$ 5,467,434	$ 5,244,905	$ 4,923,116	$ 4,520,992	$ 24,996,056	$ 20,156,447	$ 15,794,341
Gross profit	2,479,282	2,567,886	2,504,579	2,167,990	2,001,411	2,146,986	1,917,459	1,650,378
Net income	$ 542,156	$ 789,976	$ 720,196	$ 709,067	$ 586,970	$ 665,244	$ 270,650	$ 344,052	$ 2,761,395	$ 1,866,916	$ 1,211,242
Earnings (loss) per share:
Basic (in USD per share)	$ 1.23	$ 1.79	$ 1.63	$ 1.61	$ 1.34	$ 1.52	$ 0.62	$ 0.79	$ 6.26	$ 4.26	$ 2.78
Diluted (in USD per share)	$ 1.19	$ 1.74	$ 1.59	$ 1.57	$ 1.30	$ 1.47	$ 0.60	$ 0.76	$ 6.08	$ 4.13	$ 2.68