ACCUMULATED OTHER COMPREHENSIVE (LOSS) INCOME - Summary of components of accumulated other comprehensive (loss) income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31	$ (17,833)		$ (10,115)
Change during the period:
Before-tax amount	(998)		(527)
Tax benefit	(11)		20
Reclassification adjustment, net of taxes:
Amortization of net loss	125	[1]	84	[1]
Total activity for the period	(884)		(423)
Balance at March 31	(18,717)		(10,538)
Pension Adjustment
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31	(16,246)		(9,760)
Change during the period:
Before-tax amount
Tax benefit
Reclassification adjustment, net of taxes:
Amortization of net loss	125	[1]	84	[1]
Total activity for the period	125		84
Balance at March 31	(16,121)		(9,676)
Unrealized Gain (Loss) On Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31	(98)		10
Change during the period:
Before-tax amount	31		(56)
Tax benefit	(11)		20
Reclassification adjustment, net of taxes:
Amortization of net loss		[1]		[1]
Total activity for the period	20		(36)
Balance at March 31	(78)		(26)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance at December 31	(1,489)		(365)
Change during the period:
Before-tax amount	(1,029)		(471)
Tax benefit
Reclassification adjustment, net of taxes:
Amortization of net loss		[1]		[1]
Total activity for the period	(1,029)		(471)
Balance at March 31	$ (2,518)		$ (836)

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