COMPONENTS OF THE COMPANY'S CONDENSED CONSOLIDATED BALANCE SHEETS Changes in Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Sep. 30, 2016		Sep. 30, 2015		Sep. 30, 2016		Sep. 30, 2015
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (1,527)		$ (1,167)		$ (1,851)		$ (1,136)
Other comprehensive income (loss) before reclassifications	(399)		60		(155)		1
Amounts reclassified from accumulated other comprehensive income (loss)	41		64		121		92
Net-current period other comprehensive income (loss)	(358)		124		(34)		93
Ending balance	(1,885)		(1,043)		(1,885)		(1,043)
Unrealized Gains and Losses on Marketable Securities
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	164		46		(97)		83
Other comprehensive income (loss) before reclassifications	(145)		20		116		(17)
Amounts reclassified from accumulated other comprehensive income (loss)	0		0		0		0
Net-current period other comprehensive income (loss)	(145)		20		116		(17)
Ending balance	19		66		19		66
Defined Benefit Pension Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(1,504)		(1,212)		(1,584)		(1,240)
Other comprehensive income (loss) before reclassifications	0		0		0		0
Amounts reclassified from accumulated other comprehensive income (loss)	41	[1]	64	[1]	121	[2]	92	[2]
Net-current period other comprehensive income (loss)	41		64		121		92
Ending balance	(1,463)		(1,148)		(1,463)		(1,148)
Foreign Currency Items
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(187)		(1)		(170)		21
Other comprehensive income (loss) before reclassifications	(254)		40		(271)		18
Amounts reclassified from accumulated other comprehensive income (loss)	0		0		0		0
Net-current period other comprehensive income (loss)	(254)		40		(271)		18
Ending balance	$ (441)		$ 39		$ (441)		$ 39

[1] This component of accumulated other comprehensive income (loss) is included in the computation of net periodic pension cost for the three months ended September 30, 2016 and 2015.

[2] This component of accumulated other comprehensive income (loss) is included in the computation of net periodic pension cost for the nine months ended September 30, 2016 and 2015.