Accumulated Other Comprehensive Loss - Reclassification of component (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Realized (gains) losses on sale of securities
Net realized (gains) losses on investment securities	$ 0	$ 0
Provision for income taxes	0	0
Net of tax	0	0
Amortization of estimated defined benefit pension plan loss
Other expense	648	366
Provision for income taxes	(136)	(77)
Net of tax	512	289
Total reclassifications for the period	$ 512	$ 289

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Amount after tax and 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, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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Amount before tax 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 gain (loss) realized upon the sale of available-for-sale securities.

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Amount, after tax, of reclassification adjustment from accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan.

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Amount after tax of reclassification adjustments of other comprehensive income (loss).

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