NET INCOME PER SHARE (Tables)

6 Months Ended

Jun. 30, 2017

Earnings Per Share [Abstract]

Reconciliation of the weighted average number of shares outstanding used in calculating diluted earnings per share

A reconciliation of the weighted-average number of shares outstanding used in calculating diluted earnings per share is as follows (in thousands): 

	Three Months Ended June 30,		Six Months Ended June 30,
	2017	2016	2017	2016
Weighted-average number of basic common shares outstanding	49,131	49,604	49,161	49,617
Weighted-average dilutive stock options, restricted stock units and performance share units	206	167	221	230
Assumed conversion of Convertible Senior Notes	719	288	667	258
Weighted-average number of diluted common and common equivalent shares outstanding	50,056	50,059	50,049	50,105
Anti-dilutive potential common shares	2,075	2,591	2,118	2,566