CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Foreign currency translation adjustments, tax			$ 0
Unrealized gains (losses) on marketable securities arising during period, net of tax	$ (578)	$ 1,629	1,659
Reclassification adjustment for (gains) losses included in net income, net of tax	(277)	(665)	(192)
Amortization of prior service credit, net of tax	$ (2)	$ (2)	$ (43)

Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive (income) loss for prior service cost (credit) of defined benefit plan.

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Amount of tax expense (benefit), after 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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-Publisher FASB
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Amount of tax expense (benefit) of reclassification adjustment from accumulated other comprehensive income for unrealized gain (loss) realized upon the sale of available-for-sale securities.

+ References

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- Definition

Amount, before adjustment, of tax expense (benefit) for unrealized holding gain (loss) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Excludes tax expense (benefit) for unrealized gain (loss) on investment in debt security measured at amortized cost (held-to-maturity) from transfer to available-for-sale.

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