EARNINGS PER SHARE (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Basic earnings per share:
Net income	$ 6,343		$ 12,363
Weighted-average common shares (in Shares)	29,309,000		30,239,000
Basic earnings per share (in dollars per share)	$ 0.22		$ 0.41
Diluted earnings per share:
Net income	$ 6,343		$ 12,363
Weighted-average common shares (in Shares)	29,309,000		30,239,000
Effect of dilutive securities:
Employee stock plans (shares)	749,000	[1]	928,000	[1]
Diluted weighted-average common shares (in Shares)	30,058,000	[1]	31,167,000	[1]
Diluted earnings per share (in dollars per share)	$ 0.21	[1]	$ 0.40	[1]
Stock awards excluded in the computation of diluted earnings per share	0		0

[1] The Company includes the shares underlying performance-based awards in the calculation of diluted earnings per share if the performance conditions have been satisfied as of the end of the reporting period and excludes such shares when the necessary conditions have not been met. The Company has excluded the shares underlying the 2015 and 2014 awards in the 2015 and 2014 calculations, respectively, as those shares were not contingently issuable as of the end of the period.