CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Parenthetical) - shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Issuance of shares of Common Stock upon exercise of stock options and restricted stock units and performance shares	2,677,810	2,657,892	1,624,376
Issuance of shares of Common Stock under the ESPP	258,453	239,590	233,712
Issuance of shares of Common Stock for services rendered	6,350	5,688	4,905
Convertible Senior Notes 0.375 Percent Due 2018
Issuance of shares of Common Stock upon conversion of convertible senior notes			148,761
Convertible Senior Notes 1.25 Percent Due 2020
Issuance of shares of Common Stock upon conversion of convertible senior notes	368,886