NET INCOME PER SHARE (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended				12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Oct. 23, 2013	Dec. 31, 2013 Outstanding Stock Awards	Dec. 31, 2012 Outstanding Stock Awards	Dec. 31, 2011 Outstanding Stock Awards	Dec. 31, 2013 Convertible Debt.	Dec. 31, 2012 Convertible Debt.	Dec. 31, 2011 Convertible Debt.	Dec. 31, 2006 Convertible Debt 0.75 Percent Due September 2013 [Member]
Anti-dilutive Securities Excluded From Computation Of Earnings Per Share
Weighted average number of basic common shares outstanding (in shares)	50,924,000	49,840,000	49,654,000
Weighted average dilutive stock options, restricted stock units and performance share units (in shares)	382,000	501,000	828,000
Assumed conversion of Convertible Senior Notes (in shares)	1,107,000	985,000	729,000
Weighted average number of diluted common and common equivalent shares outstanding (in shares)	52,413,000	51,326,000	51,211,000
Anti-dilutive potential common shares (in shares)					2,384,000	2,202,000	1,453,000	2,000,000	2,000,000	1,200,000
Aggregate principal amount											$ 172.5
Option indexed to issuer's equity, settlement alternatives, shares, at Fair Value				42,160