EARNINGS PER SHARE (Details) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Income (Numerator)
Net income	$ 43,994	$ 70,703
Net income attributable to noncontrolling interests	(871)	(13,501)
Numerator for basic and diluted earnings per common share available to common shareholders	$ 43,123	$ 57,202
Shares (Denominator)
Weighted-average common shares outstanding (shares)	101,899	92,630
Dilutive effect of stock-settled appreciation rights, restricted stock awards and outstanding stock options (shares)	1,018	1,062
Weighted-average common and common equivalent shares outstanding (shares)	102,917	93,692

Amount after tax of income (loss) from continuing operations attributable to the noncontrolling interest.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
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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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