EARNINGS PER SHARE (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Earnings per share — Basic:
Earnings from continuing operations	$ 43,519	$ 51,395	$ 77,451	$ 89,931
Less: Earnings allocated to unvested stock	(158)	(186)	(277)	(318)
Earnings from continuing operations available to common shareholders — Basic	$ 43,361	$ 51,209	$ 77,174	$ 89,613
Weighted average common shares outstanding - Basic (shares)	52,370	52,663	52,388	52,804
Earnings from continuing operations per common share - Basic (in dollars per share)	$ 0.83	$ 0.97	$ 1.47	$ 1.70
Earnings per share — Diluted:
Earnings from continuing operations	$ 43,519	$ 51,395	$ 77,451	$ 89,931
Less: Earnings allocated to unvested stock	(158)	(186)	(277)	(318)
Earnings from continuing operations available to common shareholders — Diluted	$ 43,361	$ 51,209	$ 77,174	$ 89,613
Weighted average common shares outstanding - Basic (shares)	52,370	52,663	52,388	52,804
Effect of dilutive equity awards (shares)	254	244	337	348
Weighted average common shares outstanding — Diluted (shares)	52,624	52,907	52,725	53,152
Earnings from continuing operations per common share - Diluted (in dollars per share)	$ 0.82	$ 0.97	$ 1.46	$ 1.69
Anti-dilutive equity awards not included above (shares)	1,447	1,231	1,247	911