SHAREHOLDERS' DEFICIT AND ACCUMULATED OTHER COMPREHENSIVE INCOME (LOSS) - Changes in Accumulated Other Comprehensive Income by component (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2016 USD ($)
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	$ (171,300)
Other comprehensive income before reclassifications	18,385
Amounts reclassified from accumulated other comprehensive income (loss)	1,018
Balance at end of period	(151,897)
Defined benefit plans adjustment | Pension
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(34,558)
Other comprehensive income before reclassifications	172
Amounts reclassified from accumulated other comprehensive income (loss)	818
Balance at end of period	(33,568)
Defined benefit plans adjustment | Postretirement Medical Benefits
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(31,086)
Other comprehensive income before reclassifications	(688)
Amounts reclassified from accumulated other comprehensive income (loss)	200
Balance at end of period	(31,574)
Available for sale securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(1,325)
Other comprehensive income before reclassifications	(281)
Amounts reclassified from accumulated other comprehensive income (loss)	0
Balance at end of period	(1,606)
Foreign currency translation adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(69,901)
Other comprehensive income before reclassifications	19,239
Balance at end of period	(50,662)
Tax effect of other comprehensive income gains
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at beginning of period	(34,430)
Other comprehensive income before reclassifications	(57)
Balance at end of period	$ (34,487)