Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 9,466	$ 8,998	$ 18,884	$ 16,707
Unrealized gains (losses) on securities:
Unrealized (losses) gains arising during period	232	288	(235)	501
Less: reclassification adjustment for gains included in net income			5	(142)
Total unrealized (losses) gains on securities	232	288	(230)	359
Accretion of net unrealized losses transferred	203	253	419	634
Defined benefit pension plans:
Amortization of prior service cost and loss included in net periodic benefit cost	264	292	527	585
Other comprehensive income	699	833	716	1,578
Comprehensive income	$ 10,165	$ 9,831	$ 19,600	$ 18,285

Amortization of prior service cost and loss included in net periodic benefit cost.

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Other comprehensive income accretion on unrealized loss for securities transferred from available for sale to held to maturity net of tax.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount after tax, before reclassification adjustments, of unrealized holding gain (loss) on available-for-sale securities and unrealized holding gain (loss) related to transfers of securities into the available-for-sale classification and out of the held-to-maturity classification.

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

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Amount after 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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