EARNINGS PER SHARE (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015
Income (Numerator)
Net Income	$ 25,629	$ 24,836
Net (income) loss attributable to noncontrolling interests	(1,489)	(554)
Numerator for diluted earnings per common share available to common shareholders	$ 24,140	$ 24,282
Shares (Denominator)
Weighted-average common shares outstanding (shares)	94,701,000	95,131,000
Dilutive effect of stock-settled appreciation rights, restricted stock awards and outstanding stock options (shares)	913,000	640,000
Weighted-average common and common equivalent shares outstanding (shares)	95,614,000	95,771,000
Additional Disclosures
Potentially antidilutive dilutive securities excluded from calculation of diluted earnings per share (shares)	407,479	325,000

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.

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Amount of income (loss) from continuing operations attributable to the noncontrolling interest. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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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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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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