ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Summary of components of accumulated other comprehensive (loss) income (Details) - USD ($) $ in Thousands		6 Months Ended
		Jun. 30, 2016	Jun. 30, 2015
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance at December 31		$ (17,969)	$ (17,833)
Change during the period:
Before-tax amount		842	(879)
Tax benefit		5	1
Reclassification adjustment, net of taxes:
Amortization of net loss	[1]	254	250
Total activity for the period		1,101	(628)
Balance at June 30		(16,868)	(18,461)
Pension Adjustment
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance at December 31		(14,715)	(16,246)
Change during the period:
Before-tax amount
Tax benefit
Reclassification adjustment, net of taxes:
Amortization of net loss	[1]	254	250
Total activity for the period		254	250
Balance at June 30		(14,461)	(15,996)
Unrealized Gain (Loss) On Securities
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance at December 31		36	(98)
Change during the period:
Before-tax amount		(14)	(3)
Tax benefit		5	1
Reclassification adjustment, net of taxes:
Amortization of net loss	[1]
Total activity for the period		(9)	(2)
Balance at June 30		27	(100)
Foreign Currency Translation
Accumulated Other Comprehensive Income Loss [Roll Forward]
Balance at December 31		(3,290)	(1,489)
Change during the period:
Before-tax amount		856	(876)
Tax benefit
Reclassification adjustment, net of taxes:
Amortization of net loss	[1]
Total activity for the period		856	(876)
Balance at June 30		$ (2,434)	$ (2,365)

[1] Reported as part of selling, general and administrative expenses.