NET INCOME PER SHARE (Details) - shares shares in Thousands	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Weighted-average number of basic common shares outstanding	51,909	52,153
Weighted-average dilutive stock options, restricted stock units and performance share units	257	317
Assumed conversion of convertible debt (in shares)	240	548
Weighted average number of diluted common and common equivalent shares outstanding (in shares)	52,406	53,018
Unvested Stock Awards Outstanding and Convertible Debt Securities [Member]
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Anti-dilutive potential common shares	2,616	2,069
Convertible Debt [Member]
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Anti-dilutive potential common shares	2,100

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Antidilution
-URI http://asc.fasb.org/extlink&oid=6505113

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Diluted Earnings Per Share
-URI http://asc.fasb.org/extlink&oid=6510752

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Contingent Stock Agreement
-URI http://asc.fasb.org/extlink&oid=6508534

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Paragraph 1
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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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