Consolidated Statements of Changes in Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Cumulative Effect on Retained Earnings, Tax	$ 33	$ 1,507	$ 0
Unrealized loss on investment, taxes	97	0	466
Other Comprehensive Income (Loss), Pension and Other Postretirement Benefit Plans, Plan Amendments, Tax Effect	$ 22	$ 0	$ 0
Common stock, dividends per share, paid	$ 1.20	$ 1.12	$ 1.04

Aggregate dividends paid during the period for each share of common stock outstanding.

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Amount of the related income tax effect of a cumulative effect on retained earnings.

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Tax effect of plan amendments that occurred that has not been recognized in net periodic benefit cost.

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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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