GENERAL (Schedule of Changes in AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Beginning balance	$ (1,135)	$ (25)	$ (611)	$ (324)
Net other comprehensive income before reclassifications	(3)	257	(527)	951
Net gains reclassified from accumulated other comprehensive loss		(599)		(994)
Net current period other comprehensive income (loss)	(3)	(342)	(527)	(43)
Ending balance	(1,138)	(367)	(1,138)	(367)
Net unrealized gains (losses) on available-for-sale marketable securities [Member]
Beginning balance	(943)	(108)	(433)	(136)
Net other comprehensive income before reclassifications	(6)	5	(516)	33
Net gains reclassified from accumulated other comprehensive loss
Net current period other comprehensive income (loss)	(6)	5	(516)	33
Ending balance	(949)	(103)	(949)	(103)
Unrealized gains (losses) on cash flow hedges [Member]
Beginning balance		533		19
Net other comprehensive income before reclassifications		66		975
Net gains reclassified from accumulated other comprehensive loss		(599)		(994)
Net current period other comprehensive income (loss)		(533)		(19)
Ending balance
Net unrealized gains (losses) on foreign currency translation [Member]
Beginning balance	(192)	(450)	(178)	(207)
Net other comprehensive income before reclassifications	3	186	(11)	(57)
Net gains reclassified from accumulated other comprehensive loss
Net current period other comprehensive income (loss)	3	186	(11)	(57)
Ending balance	$ (189)	$ (264)	$ (189)	$ (264)

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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