Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Reclassification adjustment for realized gains on marketable securities included in net income, tax	$ 0	$ 0	$ (1,326)
Reclassification adjustment for unrealized losses on marketable securities included in net income, tax	0	0	16
Changes in fair value of marketable securities, tax	$ 0	$ 0	$ (687)

Amount of tax expense (benefit), after reclassification adjustments, of appreciation (loss) in value of unsold available-for-sale securities, attributable to parent entity. Excludes amounts related to other than temporary impairment (OTTI) loss.

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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.

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Amount of tax (expense) benefit of reclassification adjustment from accumulated other comprehensive income for unrealized loss realized upon the write-down of available-for-sale securities.

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