Organization and Significant Accounting Policies - Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	$ (768)
Foreign currency translation adjustments	(513)	$ 802	$ (6)
Unrealized losses from marketable securities, net of tax	(4)	(2)	(6)
Balance, end of period	(1,285)	(768)
Foreign currency translation
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(772)	(1,574)
Foreign currency translation adjustments	(513)	802
Balance, end of period	(1,285)	(772)	(1,574)
Available-for-sale marketable securities
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	4	6
Unrealized losses from marketable securities, net of tax	(4)	(2)
Balance, end of period	0	4	6
Accumulated Other Comprehensive Income (Loss)
Increase (Decrease) in Accumulated Other Comprehensive Income [Roll Forward]
Balance, beginning of period	(768)
Foreign currency translation adjustments		802	(6)
Unrealized losses from marketable securities, net of tax		(2)	$ (6)
Balance, end of period	$ (1,285)	$ (768)

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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-Publisher FASB
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-Topic 220
-SubTopic 10
-Section 45
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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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- Definition

Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

+ References

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities.

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