DEBT (Schedule of Long Term Debt) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Total debt	$ 791,233
Current maturities of long-term debt	0	$ 129,706
LONG-TERM DEBT	791,233	$ 621,849
Senior Notes due 2022 at a fixed interest rate of 3.75%
Debt Instrument [Line Items]
Total debt	$ 325,000
Interest rate	3.75%
Term Credit Agreement borrowings due 2024 at a variable interest rate of 1.8% at September 30, 2015
Debt Instrument [Line Items]
Total debt	$ 170,000
Interest rate	1.80%
Revolving Credit Facility borrowings due 2020 at a variable interest rate of 1.4% at September 30, 2015
Debt Instrument [Line Items]
Total debt	$ 67,000
Interest rate	1.40%
Mortgage notes due 2017 at fixed interest rates of 4.35%
Debt Instrument [Line Items]
Total debt	$ 42,739
Interest rate	4.35%
Solid waste bond due 2020 at a variable interest rate of 1.3% at September 30, 2015
Debt Instrument [Line Items]
Total debt	$ 15,000
Interest rate	1.30%
New Zealand JV Revolving Credit Facility due 2016 at a variable interest rate of 4.83% at September 30, 2015
Debt Instrument [Line Items]
Total debt	$ 149,860
Interest rate	4.83%
New Zealand JV noncontrolling interest shareholder loan at 0% interest rate
Debt Instrument [Line Items]
Total debt	$ 21,634
Interest rate	0.00%