COMPONENTS OF THE COMPANY'S CONDENSED CONSOLIDATED BALANCE SHEETS Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (1,851)	$ (1,136)
Other comprehensive income (loss) before reclassifications	159	91
Amounts reclassified from accumulated other comprehensive income (loss)	40	14
Net-current period other comprehensive income (loss)	199	105
Ending balance	(1,652)	(1,031)
Unrealized Gains and Losses on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(97)	83
Other comprehensive income (loss) before reclassifications	213	56
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Net-current period other comprehensive income (loss)	213	56
Ending balance	116	139
Defined Benefit Pension Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(1,584)	(1,240)
Other comprehensive income (loss) before reclassifications	0	0
Amounts reclassified from accumulated other comprehensive income (loss)	40	14
Net-current period other comprehensive income (loss)	40	14
Ending balance	(1,544)	(1,226)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(170)	21
Other comprehensive income (loss) before reclassifications	(54)	35
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Net-current period other comprehensive income (loss)	(54)	35
Ending balance	$ (224)	$ 56