NET INCOME PER SHARE (Details) - shares shares in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Weighted-average number of basic common shares outstanding	51,589	52,397	51,748	52,275
Weighted-average dilutive stock options, restricted stock units and performance share units	229	188	273	271
Assumed conversion of convertible debt (in shares)	220	370	232	458
Weighted average number of diluted common and common equivalent shares outstanding (in shares)	52,038	52,955	52,253	53,004
Unvested Stock Awards Outstanding and Convertible Debt Securities [Member]
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Anti-dilutive potential common shares	2,775	2,161	2,769	2,077
Convertible Debt [Member]
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Anti-dilutive potential common shares	2,100		2,100