Consolidated Statements of Comprehensive Income (Parentheticals) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net unrealized gain (loss) arising during the period, tax	$ (806)	$ (570)	$ (1,106)
Reclassification adjustment for net losses (gains) on sales realized in net income, tax	(1)	(35)	27
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Investment Transferred from Available-for-sale to Equity Method, Tax	(88)	0	0
Unrealized investment gain (loss), tax	(895)	(605)	(1,079)
Change in unfunded pension liability related to unrealized loss, prior service cost and transition obligation, tax expense (benefit)	$ 72	$ (54)	$ 5

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

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Amount of tax (expense) benefit for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

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

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