STOCKHOLDERS' EQUITY (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Accumulated other comprehensive loss, pre-tax amounts:
Unrecognized net periodic benefit costs	$ (34,733)	$ (86,737)
Foreign currency translation	(884)	(662)
Total pre-tax amount	(35,617)	(87,399)
Accumulated other comprehensive loss, after-tax amounts:
Unrecognized net periodic benefit costs	(25,194)	(56,968)
Foreign currency translation	(539)	(404)
Total after-tax amount	$ (25,733)	$ (57,372)