CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS’ EQUITY (Parenthetical) - shares	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Issuance of shares of Common Stock upon exercise of stock options and restricted stock units	1,044,745	623,709
Issuance of shares of Common Stock for services rendered	1,200	1,032
Convertible Senior Notes 0.375 Percent Due 2018
Issuance of shares of Common Stock upon conversion of convertible senior notes		539

Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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