EARNINGS PER SHARE (Computation of Basic and Diluted Earnings Per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator (basic and diluted):
Net income	$ 585,451	$ 531,667	$ 1,087,060	$ 832,105
Denominator:
Denominator for basic earnings per share - weighted-average shares	69,618	74,205	69,997	74,611
Effect of stock options	646	628	643	635
Denominator for diluted earnings per share - weighted-average shares and assumed conversion	70,264	74,833	70,640	75,246
Earnings per share - basic	$ 8.41	$ 7.16	$ 15.53	$ 11.15
Earnings per share - assuming dilution	$ 8.33	$ 7.10	$ 15.39	$ 11.06
Antidilutive stock options	122	341	187	348
Weighted-average exercise price per share of antidilutive stock options	$ 463.76	$ 378.84	$ 449.20	$ 378.29