STOCKHOLDERS' EQUITY (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Changes in accumulated other comprehensive income (loss), net of tax
Beginning Balance	$ (24,880)	$ (14,503)	$ (3,161)
Before-Tax Amount	53,796	(18,184)	(17,007)
Tax Benefit (Expense)	(23,014)	7,807	5,665
Total other comprehensive income (loss), net of tax	30,782	(10,377)	(11,342)
Ending Balance	5,902	(24,880)	(14,503)
Pension and other postretirement liability adjustment
Changes in accumulated other comprehensive income (loss), net of tax
Beginning Balance	(45,958)	(33,600)	(22,161)
Before-Tax Amount	59,743	(20,165)	(18,678)
Tax Benefit (Expense)	(23,014)	7,807	7,239
Total other comprehensive income (loss), net of tax	36,729	(12,358)	(11,439)
Ending Balance	(9,229)	(45,958)	(33,600)
Foreign currency translation adjustment
Changes in accumulated other comprehensive income (loss), net of tax
Beginning Balance	21,078	19,097	21,622
Before-Tax Amount	(5,947)	1,981	(2,525)
Tax Benefit (Expense)	0	0	0
Total other comprehensive income (loss), net of tax	(5,947)	1,981	(2,525)
Ending Balance	15,131	21,078	19,097
Change in the fair value of interest rate swap contracts
Changes in accumulated other comprehensive income (loss), net of tax
Beginning Balance			(2,622)
Before-Tax Amount			4,196
Tax Benefit (Expense)			(1,574)
Total other comprehensive income (loss), net of tax			2,622
Ending Balance			$ 0